Expression (Mapbox Maps SDK for Android 6.2.1 Reference)

java.lang.Object
- com.mapbox.mapboxsdk.style.expressions.Expression

Direct Known Subclasses:

Expression.ExpressionLiteral, Expression.Interpolator
```
public class Expression
extends Object
```
The value for any layout property, paint property, or filter may be specified as an expression. An expression defines a formula for computing the value of the property using the operators described below. The set of expression operators provided by Mapbox GL includes:
- Element
- Mathematical operators for performing arithmetic and other operations on numeric values
- Logical operators for manipulating boolean values and making conditional decisions
- String operators for manipulating strings
- Data operators, providing access to the properties of source features
- Camera operators, providing access to the parameters defining the current map view
Expressions are represented as JSON arrays. The first element of an expression array is a string naming the expression operator, e.g. "*"or "case". Subsequent elements (if any) are the arguments to the expression. Each argument is either a literal value (a string, number, boolean, or null), or another expression array.

Data expression: a data expression is any expression that access feature data -- that is, any expression that uses one of the data operators:get,has,id,geometry-type, or properties. Data expressions allow a feature's properties to determine its appearance. They can be used to differentiate features within the same layer and to create data visualizations.

Camera expression: a camera expression is any expression that uses the zoom operator. Such expressions allow the the appearance of a layer to change with the map's zoom level. Camera expressions can be used to create the appearance of depth and to control data density.

Composition: a single expression may use a mix of data operators, camera operators, and other operators. Such composite expressions allows a layer's appearance to be determined by a combination of the zoom level and individual feature properties.

Example expression:
```
 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setProperties(
   fillColor(
     interpolate( linear(), zoom(),
       stop(12, step(get("stroke-width"),
         color(Color.BLACK),
         stop(1f, color(Color.RED)),
         stop(2f, color(Color.WHITE)),
         stop(3f, color(Color.BLUE))
       )),
       stop(15, step(get("stroke-width"),
         color(Color.BLACK),
         stop(1f, color(Color.YELLOW)),
         stop(2f, color(Color.LTGRAY)),
         stop(3f, color(Color.CYAN))
       )),
       stop(18, step(get("stroke-width"),
         color(Color.BLACK),
         stop(1f, color(Color.WHITE)),
         stop(2f, color(Color.GRAY)),
         stop(3f, color(Color.GREEN))
       ))
     )
   )
 )
 
 
```

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`Expression.Array` Expression array type.
`static class`	`Expression.Converter` Converts a JsonArray or a raw expression to a Java expression.
`static class`	`Expression.ExpressionLiteral` ExpressionLiteral wraps an object to be used as a literal in an expression.
`static class`	`Expression.Interpolator` Expression interpolator type.
`static class`	`Expression.Stop` Expression stop type.

Constructor Summary

Constructors
Constructor and Description

Expression(String operator, Expression... arguments)
Creates an expression from its operator and varargs expressions.

Constructors
Constructor and Description
`Expression(String operator, Expression... arguments)` Creates an expression from its operator and varargs expressions.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static Expression`	`abs(Expression expression)` Returns the absolute value of the input.
`static Expression`	`abs(Number number)` Returns the absolute value of the input.
`static Expression`	`acos(Expression number)` Returns the arccosine of the input.
`static Expression`	`acos(Number number)` Returns the arccosine of the input.
`static Expression`	`all(Expression... input)` Returns `true` if all the inputs are `true`, `false` otherwise.
`static Expression`	`any(Expression... input)` Returns `true` if any of the inputs are `true`, `false` otherwise.
`static Expression`	`array(Expression input)` Asserts that the input is an array (optionally with a specific item type and length).
`static Expression`	`asin(Expression number)` Returns the arcsine of the input.
`static Expression`	`asin(Number number)` Returns the arcsine of the input.
`static Expression`	`at(Expression number, Expression expression)` Retrieves an item from an array.
`static Expression`	`at(Number number, Expression expression)` Retrieves an item from an array.
`static Expression`	`atan(Expression number)` Returns the arctangent of the input.
`static Expression`	`atan(Number number)` Returns the arctangent of the input.
`static Expression`	`bool(Expression... input)` Asserts that the input value is a boolean.
`static Expression`	`ceil(Expression expression)` Returns the smallest integer that is greater than or equal to the input.
`static Expression`	`ceil(Number number)` Returns the smallest integer that is greater than or equal to the input.
`static Expression`	`coalesce(Expression... input)` Evaluates each expression in turn until the first non-null value is obtained, and returns that value.
`static Expression`	`color(int color)` Expression literal utility method to convert a color int to an color expression
`static Expression`	`concat(Expression... input)` Returns a string consisting of the concatenation of the inputs.
`static Expression`	`concat(String... input)` Returns a string consisting of the concatenation of the inputs.
`static Expression`	`cos(Expression number)` Returns the cosine of the input.
`static Expression`	`cos(Number number)` Returns the cosine of the input.
`static Expression.Interpolator`	`cubicBezier(Expression x1, Expression y1, Expression x2, Expression y2)` Interpolates using the cubic bezier curve defined by the given control points.
`static Expression.Interpolator`	`cubicBezier(Number x1, Number y1, Number x2, Number y2)` Interpolates using the cubic bezier curve defined by the given control points.
`static Expression`	`division(Expression first, Expression second)` Returns the result of floating point division of the first input by the second.
`static Expression`	`division(Number first, Number second)` Returns the result of floating point division of the first input by the second.
`static Expression`	`downcase(Expression input)` Returns the input string converted to lowercase.
`static Expression`	`downcase(String input)` Returns the input string converted to lowercase.
`static Expression`	`e()` Returns the mathematical constant e.
`static Expression`	`eq(Expression compareOne, boolean compareTwo)` Returns true if the input values are equal, false otherwise.
`static Expression`	`eq(Expression compareOne, Expression compareTwo)` Returns true if the input values are equal, false otherwise.
`static Expression`	`eq(Expression compareOne, Number compareTwo)` Returns true if the input values are equal, false otherwise.
`static Expression`	`eq(Expression compareOne, String compareTwo)` Returns true if the input values are equal, false otherwise.
`boolean`	`equals(Object o)` Indicates whether some other object is "equal to" this one.
`static Expression.Interpolator`	`exponential(Expression expression)` Interpolates exponentially between the stops just less than and just greater than the input.
`static Expression.Interpolator`	`exponential(Number base)` Interpolates exponentially between the stops just less than and just greater than the input.
`static Expression`	`floor(Expression expression)` Returns the largest integer that is less than or equal to the input.
`static Expression`	`floor(Number number)` Returns the largest integer that is less than or equal to the input.
`static Expression`	`geometryType()` Gets the feature's geometry type: Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon.
`static Expression`	`get(Expression input)` Retrieves a property value from the current feature's properties, or from another object if a second argument is provided.
`static Expression`	`get(Expression key, Expression object)` Retrieves a property value from another object.
`static Expression`	`get(String input)` Retrieves a property value from the current feature's properties, or from another object if a second argument is provided.
`static Expression`	`get(String key, Expression object)` Retrieves a property value from another object.
`static Expression`	`gt(Expression compareOne, Expression compareTwo)` Returns true if the first input is strictly greater than the second, false otherwise.
`static Expression`	`gt(Expression compareOne, Number compareTwo)` Returns true if the first input is strictly greater than the second, false otherwise.
`static Expression`	`gt(Expression compareOne, String compareTwo)` Returns true if the first input is strictly greater than the second, false otherwise.
`static Expression`	`gte(Expression compareOne, Expression compareTwo)` Returns true if the first input is greater than or equal to the second, false otherwise.
`static Expression`	`gte(Expression compareOne, Number compareTwo)` Returns true if the first input is greater than or equal to the second, false otherwise.
`static Expression`	`gte(Expression compareOne, String compareTwo)` Returns true if the first input is greater than or equal to the second, false otherwise.
`static Expression`	`has(Expression key)` Tests for the presence of an property value in the current feature's properties.
`static Expression`	`has(Expression key, Expression object)` Tests for the presence of an property value from another object.
`static Expression`	`has(String key)` Tests for the presence of an property value in the current feature's properties.
`static Expression`	`has(String key, Expression object)` Tests for the presence of an property value from another object.
`int`	`hashCode()` Returns a hash code value for the expression.
`static Expression`	`heatmapDensity()` Gets the kernel density estimation of a pixel in a heatmap layer, which is a relative measure of how many data points are crowded around a particular pixel.
`static Expression`	`id()` Gets the feature's id, if it has one.
`static Expression`	`interpolate(Expression.Interpolator interpolation, Expression number, Expression... stops)` Produces continuous, smooth results by interpolating between pairs of input and output values (\"stops\").
`static Expression`	`interpolate(Expression.Interpolator interpolation, Expression number, Expression.Stop... stops)` Produces continuous, smooth results by interpolating between pairs of input and output values (\"stops\").
`static Expression`	`length(Expression expression)` Gets the length of an array or string.
`static Expression`	`length(String input)` Gets the length of an array or string.
`static Expression`	`let(Expression... input)` Binds input to named variables, which can then be referenced in the result expression using `var(String)` or `var(Expression)`.
`static Expression.Interpolator`	`linear()` interpolates linearly between the pair of stops just less than and just greater than the input.
`static Expression`	`literal(boolean bool)` Create a literal boolean expression.
`static Expression`	`literal(Number number)` Create a literal number expression.
`static Expression`	`literal(Object object)` Create a literal object expression.
`static Expression`	`literal(Object[] array)` Create a literal array expression
`static Expression`	`literal(String string)` Create a literal string expression.
`static Expression`	`ln(Expression number)` Returns the natural logarithm of the input.
`static Expression`	`ln(Number number)` Returns the natural logarithm of the input.
`static Expression`	`ln2()` Returns mathematical constant ln(2).
`static Expression`	`log10(Expression number)` Returns the base-ten logarithm of the input.
`static Expression`	`log10(Number number)` Returns the base-ten logarithm of the input.
`static Expression`	`log2(Expression number)` Returns the base-two logarithm of the input.
`static Expression`	`log2(Number number)` Returns the base-two logarithm of the input.
`static Expression`	`lt(Expression compareOne, Expression compareTwo)` Returns true if the first input is strictly less than the second, false otherwise.
`static Expression`	`lt(Expression compareOne, Number compareTwo)` Returns true if the first input is strictly less than the second, false otherwise.
`static Expression`	`lt(Expression compareOne, String compareTwo)` Returns true if the first input is strictly less than the second, false otherwise.
`static Expression`	`lte(Expression compareOne, Expression compareTwo)` Returns true if the first input is less than or equal to the second, false otherwise.
`static Expression`	`lte(Expression compareOne, Number compareTwo)` Returns true if the first input is less than or equal to the second, false otherwise.
`static Expression`	`lte(Expression compareOne, String compareTwo)` Returns true if the first input is less than or equal to the second, false otherwise.
`static Expression`	`match(Expression... input)` Selects the output whose label value matches the input value, or the fallback value if no match is found.
`static Expression`	`match(Expression input, Expression defaultOutput, Expression.Stop... stops)` Selects the output whose label value matches the input value, or the fallback value if no match is found.
`static Expression`	`max(Expression... numbers)` Returns the maximum value of the inputs.
`static Expression`	`max(Number... numbers)` Returns the maximum value of the inputs.
`static Expression`	`min(Expression... numbers)` Returns the minimum value of the inputs.
`static Expression`	`min(Number... numbers)` Returns the minimum value of the inputs.
`static Expression`	`mod(Expression first, Expression second)` Returns the remainder after integer division of the first input by the second.
`static Expression`	`mod(Number first, Number second)` Returns the remainder after integer division of the first input by the second.
`static Expression`	`neq(Expression compareOne, boolean compareTwo)` Returns true if the input values are equal, false otherwise.
`static Expression`	`neq(Expression compareOne, Expression compareTwo)` Returns true if the input values are not equal, false otherwise.
`static Expression`	`neq(Expression compareOne, Number compareTwo)` Returns `true` if the input values are not equal, `false` otherwise.
`static Expression`	`neq(Expression compareOne, String compareTwo)` Returns `true` if the input values are not equal, `false` otherwise.
`static Expression`	`not(boolean input)` Logical negation.
`static Expression`	`not(Expression input)` Logical negation.
`static Expression`	`number(Expression... input)` Asserts that the input value is a number.
`static Expression`	`object(Expression input)` Asserts that the input value is an object.
`static Expression`	`pi()` Returns the mathematical constant pi.
`static Expression`	`pow(Expression first, Expression second)` Returns the result of raising the first input to the power specified by the second.
`static Expression`	`pow(Number first, Number second)` Returns the result of raising the first input to the power specified by the second.
`static Expression`	`product(Expression... numbers)` Returns the product of the inputs.
`static Expression`	`product(Number... numbers)` Returns the product of the inputs.
`static Expression`	`properties()` Gets the feature properties object.
`static Expression`	`raw(String rawExpression)` Returns a DSL equivalent of a raw expression.
`static Expression`	`rgb(Expression red, Expression green, Expression blue)` Creates a color value from red, green, and blue components, which must range between 0 and 255, and an alpha component of 1.
`static Expression`	`rgb(Number red, Number green, Number blue)` Creates a color value from red, green, and blue components, which must range between 0 and 255, and an alpha component of 1.
`static Expression`	`rgba(Expression red, Expression green, Expression blue, Expression alpha)` Creates a color value from red, green, blue components, which must range between 0 and 255, and an alpha component which must range between 0 and 1.
`static Expression`	`rgba(Number red, Number green, Number blue, Number alpha)` Creates a color value from red, green, blue components, which must range between 0 and 255, and an alpha component which must range between 0 and 1.
`static Expression`	`round(Expression expression)` Rounds the input to the nearest integer.
`static Expression`	`round(Number number)` Rounds the input to the nearest integer.
`static Expression`	`sin(Expression number)` Returns the sine of the input.
`static Expression`	`sin(Number number)` Returns the sine of the input.
`static Expression`	`sqrt(Expression number)` Returns the square root of the input
`static Expression`	`sqrt(Number number)` Returns the square root of the input
`static Expression`	`step(Expression input, Expression defaultOutput, Expression... stops)` Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\").
`static Expression`	`step(Expression input, Expression defaultOutput, Expression.Stop... stops)` Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\").
`static Expression`	`step(Expression input, Number defaultOutput, Expression... stops)` Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\").
`static Expression`	`step(Expression input, Number defaultOutput, Expression.Stop... stops)` Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\").
`static Expression`	`step(Number input, Expression defaultOutput, Expression... stops)` Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\").
`static Expression`	`step(Number input, Expression defaultOutput, Expression.Stop... stops)` Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\").
`static Expression`	`step(Number input, Number defaultOutput, Expression... stops)` Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\").
`static Expression`	`step(Number input, Number defaultOutput, Expression.Stop... stops)` Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\").
`static Expression.Stop`	`stop(Object stop, Object value)` Produces a stop value.
`static Expression`	`string(Expression... input)` Asserts that the input value is a string.
`static Expression`	`subtract(Expression number)` Returns the result of subtracting a number from 0.
`static Expression`	`subtract(Expression first, Expression second)` Returns the result of subtracting the second input from the first.
`static Expression`	`subtract(Number number)` Returns the result of subtracting a number from 0.
`static Expression`	`subtract(Number first, Number second)` Returns the result of subtracting the second input from the first.
`static Expression`	`sum(Expression... numbers)` Returns the sum of the inputs.
`static Expression`	`sum(Number... numbers)` Returns the sum of the inputs.
`static Expression`	`switchCase(Expression... input)` Selects the first output whose corresponding test condition evaluates to true.
`static Expression`	`tan(Expression number)` Returns the tangent of the input.
`static Expression`	`tan(Number number)` Returns the tangent of the input.
`Object[]`	`toArray()` Converts the expression to Object array representation.
`static Expression`	`toBool(Expression input)` Converts the input value to a boolean.
`static Expression`	`toColor(Expression input)` Converts the input value to a color.
`static Expression`	`toNumber(Expression input)` Converts the input value to a number, if possible.
`static Expression`	`toRgba(Expression expression)` Returns a four-element array containing the input color's red, green, blue, and alpha components, in that order.
`String`	`toString()` Returns a string representation of the object that matches the definition set in the style specification.
`static Expression`	`toString(Expression input)` Converts the input value to a string.
`static Expression`	`typeOf(Expression input)` Returns a string describing the type of the given value.
`static Expression`	`upcase(Expression string)` Returns the input string converted to uppercase.
`static Expression`	`upcase(String string)` Returns the input string converted to uppercase.
`static Expression`	`var(Expression expression)` References variable bound using let.
`static Expression`	`var(String variableName)` References variable bound using let.
`static Expression`	`zoom()` Gets the current zoom level.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail
- Expression
```
public Expression(String operator,
                  Expression... arguments)
```
  Creates an expression from its operator and varargs expressions.
  
  Parameters:
  
  operator - the expression operator
  
  arguments - expressions input

Method Detail

literal

public static Expression literal(Number number)

Create a literal number expression.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(literal(10.0f))
 );

Parameters:: number - the number
Returns:: the expression

literal

public static Expression literal(String string)

Create a literal string expression.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(literal("Text"))
 );

Parameters:: string - the string
Returns:: the expression

literal

public static Expression literal(boolean bool)

Create a literal boolean expression.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillAntialias(literal(true))
 );

Parameters:: bool - the boolean
Returns:: the expression

literal
```
public static Expression literal(Object object)
```
Create a literal object expression.

Parameters:

object - the object

Returns:

the expression

literal
```
public static Expression literal(Object[] array)
```
Create a literal array expression

Parameters:

array - the array

Returns:

the expression

color

public static Expression color(int color)

Expression literal utility method to convert a color int to an color expression

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(color(Color.GREEN))
 );

Parameters:: color - the int color
Returns:: the color expression

rgb

public static Expression rgb(Expression red,
                             Expression green,
                             Expression blue)

Creates a color value from red, green, and blue components, which must range between 0 and 255, and an alpha component of 1.

If any component is out of range, the expression is an error.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
         rgb(
             literal(255.0f),
             literal(255.0f),
             literal(255.0f)
         )
     )
 );

Parameters:: red - red color expression; green - green color expression; blue - blue color expression
Returns:: expression
See Also:: Style specification

rgb

public static Expression rgb(Number red,
                             Number green,
                             Number blue)

Creates a color value from red, green, and blue components, which must range between 0 and 255, and an alpha component of 1.

If any component is out of range, the expression is an error.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
         rgb(255.0f, 255.0f, 255.0f)
     )
 );

Parameters:: red - red color value; green - green color value; blue - blue color value
Returns:: expression
See Also:: Style specification

rgba

public static Expression rgba(Expression red,
                              Expression green,
                              Expression blue,
                              Expression alpha)

Creates a color value from red, green, blue components, which must range between 0 and 255, and an alpha component which must range between 0 and 1.

If any component is out of range, the expression is an error.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
         rgba(
             literal(255.0f),
             literal(255.0f),
             literal(255.0f),
             literal(1.0f)
         )
     )
 );

Parameters:: red - red color value; green - green color value; blue - blue color value; alpha - alpha color value
Returns:: expression
See Also:: Style specification

rgba

public static Expression rgba(Number red,
                              Number green,
                              Number blue,
                              Number alpha)

Creates a color value from red, green, blue components, which must range between 0 and 255, and an alpha component which must range between 0 and 1.

If any component is out of range, the expression is an error.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
         rgb(255.0f, 255.0f, 255.0f, 1.0f)
     )
 );

Parameters:: red - red color value; green - green color value; blue - blue color value; alpha - alpha color value
Returns:: expression
See Also:: Style specification

toRgba
```
public static Expression toRgba(Expression expression)
```
Returns a four-element array containing the input color's red, green, blue, and alpha components, in that order.

Parameters:

expression - an expression to convert to a color

Returns:

expression

See Also:

Style specification

eq

public static Expression eq(Expression compareOne,
                            Expression compareTwo)

Returns true if the input values are equal, false otherwise. The inputs must be numbers, strings, or booleans, and both of the same type.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     eq(get("keyToValue"), get("keyToOtherValue"))
 );

Parameters:: compareOne - the first expression; compareTwo - the second expression
Returns:: expression
See Also:: Style specification

eq

public static Expression eq(Expression compareOne,
                            boolean compareTwo)

Returns true if the input values are equal, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     eq(get("keyToValue"), true)
 );

Parameters:: compareOne - the first expression; compareTwo - the second boolean
Returns:: expression
See Also:: Style specification

eq

public static Expression eq(Expression compareOne,
                            String compareTwo)

Returns true if the input values are equal, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     eq(get("keyToValue"), "value")
 );

Parameters:: compareOne - the first expression; compareTwo - the second number
Returns:: expression
See Also:: Style specification

eq

public static Expression eq(Expression compareOne,
                            Number compareTwo)

Returns true if the input values are equal, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     eq(get("keyToValue"), 2.0f)
 );

Parameters:: compareOne - the first expression; compareTwo - the second number
Returns:: expression
See Also:: Style specification

neq

public static Expression neq(Expression compareOne,
                             Expression compareTwo)

Returns true if the input values are not equal, false otherwise. The inputs must be numbers, strings, or booleans, and both of the same type.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     neq(get("keyToValue"), get("keyToOtherValue"))
 );

Parameters:: compareOne - the first expression; compareTwo - the second expression
Returns:: expression
See Also:: Style specification

neq

public static Expression neq(Expression compareOne,
                             boolean compareTwo)

Returns true if the input values are equal, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     neq(get("keyToValue"), true)
 );

Parameters:: compareOne - the first expression; compareTwo - the second boolean
Returns:: expression
See Also:: Style specification

neq

public static Expression neq(Expression compareOne,
                             String compareTwo)

Returns `true` if the input values are not equal, `false` otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     neq(get("keyToValue"), "value"))
 );

Parameters:: compareOne - the first expression; compareTwo - the second string
Returns:: expression
See Also:: Style specification

neq

public static Expression neq(Expression compareOne,
                             Number compareTwo)

Returns `true` if the input values are not equal, `false` otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     neq(get("keyToValue"), 2.0f))
 );

Parameters:: compareOne - the first expression; compareTwo - the second number
Returns:: expression
See Also:: Style specification

gt

public static Expression gt(Expression compareOne,
                            Expression compareTwo)

Returns true if the first input is strictly greater than the second, false otherwise. The inputs must be numbers or strings, and both of the same type.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     gt(get("keyToValue"), get("keyToOtherValue"))
 );

Parameters:: compareOne - the first expression; compareTwo - the second expression
Returns:: expression
See Also:: Style specification

gt

public static Expression gt(Expression compareOne,
                            Number compareTwo)

Returns true if the first input is strictly greater than the second, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     gt(get("keyToValue"), 2.0f)
 );

Parameters:: compareOne - the first expression; compareTwo - the second number
Returns:: expression
See Also:: Style specification

gt

public static Expression gt(Expression compareOne,
                            String compareTwo)

Returns true if the first input is strictly greater than the second, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     gt(get("keyToValue"), "value")
 );

Parameters:: compareOne - the first expression; compareTwo - the second string
Returns:: expression
See Also:: Style specification

lt

public static Expression lt(Expression compareOne,
                            Expression compareTwo)

Returns true if the first input is strictly less than the second, false otherwise. The inputs must be numbers or strings, and both of the same type.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     lt(get("keyToValue"), get("keyToOtherValue"))
 );

Parameters:: compareOne - the first expression; compareTwo - the second number
Returns:: expression
See Also:: Style specification

lt

public static Expression lt(Expression compareOne,
                            Number compareTwo)

Returns true if the first input is strictly less than the second, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     lt(get("keyToValue"), 2.0f)
 );

Parameters:: compareOne - the first expression; compareTwo - the second number
Returns:: expression
See Also:: Style specification

lt

public static Expression lt(Expression compareOne,
                            String compareTwo)

Returns true if the first input is strictly less than the second, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     lt(get("keyToValue"), "value"))
 );

Parameters:: compareOne - the first expression; compareTwo - the second string
Returns:: expression
See Also:: Style specification

gte

public static Expression gte(Expression compareOne,
                             Expression compareTwo)

Returns true if the first input is greater than or equal to the second, false otherwise. The inputs must be numbers or strings, and both of the same type.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     gte(get("keyToValue"), get("keyToOtherValue"))
 );

Parameters:: compareOne - the first expression; compareTwo - the second expression
Returns:: expression
See Also:: Style specification

gte

public static Expression gte(Expression compareOne,
                             Number compareTwo)

Returns true if the first input is greater than or equal to the second, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     gte(get("keyToValue"), 2.0f)
 );

Parameters:: compareOne - the first expression; compareTwo - the second number
Returns:: expression
See Also:: Style specification

gte

public static Expression gte(Expression compareOne,
                             String compareTwo)

Returns true if the first input is greater than or equal to the second, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     neq(get("keyToValue"), "value")
 );

Parameters:: compareOne - the first expression; compareTwo - the second string
Returns:: expression
See Also:: Style specification

lte

public static Expression lte(Expression compareOne,
                             Expression compareTwo)

Returns true if the first input is less than or equal to the second, false otherwise. The inputs must be numbers or strings, and both of the same type.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     lte(get("keyToValue"), get("keyToOtherValue"))
 );

Parameters:: compareOne - the first expression; compareTwo - the second expression
Returns:: expression
See Also:: Style specification

lte

public static Expression lte(Expression compareOne,
                             Number compareTwo)

Returns true if the first input is less than or equal to the second, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     lte(get("keyToValue"), 2.0f)
 );

Parameters:: compareOne - the first expression; compareTwo - the second number
Returns:: expression
See Also:: Style specification

lte

public static Expression lte(Expression compareOne,
                             String compareTwo)

Returns true if the first input is less than or equal to the second, false otherwise.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     lte(get("keyToValue"), "value")
 );

Parameters:: compareOne - the first expression; compareTwo - the second string
Returns:: expression
See Also:: Style specification

all
```
public static Expression all(Expression... input)
```
Returns `true` if all the inputs are `true`, `false` otherwise.
The inputs are evaluated in order, and evaluation is short-circuiting: once an input expression evaluates to `false`, the result is `false` and no further input expressions are evaluated.

Example usage:
```
 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     all(get("keyToValue"), get("keyToOtherValue"))
 );
 
 
```
Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

any
```
public static Expression any(Expression... input)
```
Returns `true` if any of the inputs are `true`, `false` otherwise.
The inputs are evaluated in order, and evaluation is short-circuiting: once an input expression evaluates to `true`, the result is `true` and no further input expressions are evaluated.

Example usage:
```
 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     any(get("keyToValue"), get("keyToOtherValue"))
 );
 
 
```
Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

not
```
public static Expression not(Expression input)
```
Logical negation. Returns `true` if the input is `false`, and `false` if the input is `true`.
Example usage:
```
 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     not(get("keyToValue"))
 );
 
 
```
Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

not
```
public static Expression not(boolean input)
```
Logical negation. Returns `true` if the input is `false`, and `false` if the input is `true`.
Example usage:
```
 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     not(false)
 );
 
 
```
Parameters:

input - boolean input

Returns:

expression

See Also:

Style specification

switchCase

public static Expression switchCase(Expression... input)

Selects the first output whose corresponding test condition evaluates to true.

For each case a condition and an output should be provided. The last parameter should provide the default output.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     iconSize(
         switchCase(
             get(KEY_TO_BOOLEAN), literal(3.0f),
             get(KEY_TO_OTHER_BOOLEAN), literal(5.0f)
             literal(1.0f) // default value
         )
     )
 );

Parameters:: input - expression input
Returns:: expression
See Also:: Style specification

match
```
public static Expression match(Expression... input)
```
Selects the output whose label value matches the input value, or the fallback value if no match is found. The `input` can be any string or number expression. Each label can either be a single literal value or an array of values. If types of the input and keys don't match, or the input value doesn't exist, the expresion will fail without falling back to the default value.
Example usage:
```
 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textColor(
         match(get("keyToValue"),
             literal(1), rgba(255, 0, 0, 1.0f),
             literal(2), rgba(0, 0, 255.0f, 1.0f),
             rgba(0.0f, 255.0f, 0.0f, 1.0f)
         );
     )
 );
 
 
```
Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

match

public static Expression match(Expression input,
                               Expression defaultOutput,
                               Expression.Stop... stops)

Selects the output whose label value matches the input value, or the fallback value if no match is found. The `input` can be any string or number expression. Each label can either be a single literal value or an array of values. If types of the input and keys don't match, or the input value doesn't exist, the expresion will fail without falling back to the default value.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textColor(
         match(get("keyToValue"),
             literal(1), rgba(255, 0, 0, 1.0f),
             literal(2), rgba(0, 0, 255.0f, 1.0f),
             rgba(0.0f, 255.0f, 0.0f, 1.0f)
         );
     )
 );

Parameters:: input - expression input
Returns:: expression
See Also:: Style specification

coalesce

public static Expression coalesce(Expression... input)

Evaluates each expression in turn until the first non-null value is obtained, and returns that value.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textColor(
         coalesce(
             get("keyToNullValue"),
             get("keyToNonNullValue")
         );
     )
 );

Parameters:: input - expression input
Returns:: expression
See Also:: Style specification

properties

public static Expression properties()

Gets the feature properties object.

Note that in some cases, it may be more efficient to use get(Expression)} instead.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(get("key-to-value", properties())))
 );

Returns:: expression
See Also:: Style specification

geometryType

public static Expression geometryType()

Gets the feature's geometry type: Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(concat(get("key-to-value"), literal(" "), geometryType())
 );

Returns:: expression
See Also:: Style specification

id

public static Expression id()

Gets the feature's id, if it has one.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(id())
 );

Returns:: expression
See Also:: Style specification

heatmapDensity

public static Expression heatmapDensity()

Gets the kernel density estimation of a pixel in a heatmap layer, which is a relative measure of how many data points are crowded around a particular pixel. Can only be used in the `heatmap-color` property.

Example usage:

 
 HeatmapLayer layer = new HeatmapLayer("layer-id", "source-id");
 layer.setProperties(
     heatmapColor(interpolate(linear(), heatmapDensity(),
         literal(0), rgba(33, 102, 172, 0),
         literal(0.2), rgb(103, 169, 207),
         literal(0.4), rgb(209, 229, 240),
         literal(0.6), rgb(253, 219, 199),
         literal(0.8), rgb(239, 138, 98),
         literal(1), rgb(178, 24, 43)
     )
 )

Returns:: expression
See Also:: Style specification

at
```
public static Expression at(Expression number,
                            Expression expression)
```
Retrieves an item from an array.

Parameters:

number - the index expression

expression - the array expression

Returns:

expression

See Also:

Style specification

at
```
public static Expression at(Number number,
                            Expression expression)
```
Retrieves an item from an array.

Parameters:

number - the index expression

expression - the array expression

Returns:

expression

See Also:

Style specification

get
```
public static Expression get(Expression input)
```
Retrieves a property value from the current feature's properties, or from another object if a second argument is provided. Returns null if the requested property is missing.
Example usage:
```
 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(get("key-to-feature"))
 );
 
 
```
Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

get
```
public static Expression get(String input)
```
Retrieves a property value from the current feature's properties, or from another object if a second argument is provided. Returns null if the requested property is missing.
Example usage:
```
 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(get("key-to-feature"))
 );
 
 
```
Parameters:

input - string input

Returns:

expression

See Also:

Style specification

get

public static Expression get(Expression key,
                             Expression object)

Retrieves a property value from another object. Returns null if the requested property is missing.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(get("key-to-property", get("key-to-object")))
 );

Parameters:: key - a property value key; object - an expression object
Returns:: expression
See Also:: Style specification

get

public static Expression get(String key,
                             Expression object)

Retrieves a property value from another object. Returns null if the requested property is missing.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(get("key-to-property", get("key-to-object")))
 );

Parameters:: key - a property value key; object - an expression object
Returns:: expression
See Also:: Style specification

has
```
public static Expression has(Expression key)
```
Tests for the presence of an property value in the current feature's properties.
Example usage:
```
 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     has(get("keyToValue"))
 );
 
 
```
Parameters:

key - the expression property value key

Returns:

expression

See Also:

Style specification

has
```
public static Expression has(String key)
```
Tests for the presence of an property value in the current feature's properties.
Example usage:
```
 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     has("keyToValue")
 );
 
 
```
Parameters:

key - the property value key

Returns:

expression

See Also:

Style specification

has

public static Expression has(Expression key,
                             Expression object)

Tests for the presence of an property value from another object.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     has(get("keyToValue"), get("keyToObject"))
 );

Parameters:: key - the expression property value key; object - an expression object
Returns:: expression
See Also:: Style specification

has

public static Expression has(String key,
                             Expression object)

Tests for the presence of an property value from another object.

Example usage:

 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setFilter(
     has("keyToValue", get("keyToObject))
 );

Parameters:: key - the property value key; object - an expression object
Returns:: expression
See Also:: Style specification

length
```
public static Expression length(Expression expression)
```
Gets the length of an array or string.

Parameters:

expression - an expression object or expression string

Returns:

expression

See Also:

Style specification

length
```
public static Expression length(String input)
```
Gets the length of an array or string.

Parameters:

input - a string

Returns:

expression

See Also:

Style specification

ln2

public static Expression ln2()

Returns mathematical constant ln(2).

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(product(literal(10.0f), ln2())))
 );

Returns:: expression
See Also:: Style specification

pi

public static Expression pi()

Returns the mathematical constant pi.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(product(literal(10.0f), pi())))
 );

Returns:: expression
See Also:: Style specification

e

public static Expression e()

Returns the mathematical constant e.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(product(literal(10.0f), e())))
 );

Returns:: expression
See Also:: Style specification

sum

public static Expression sum(Expression... numbers)

Returns the sum of the inputs.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(sum(literal(10.0f), ln2(), pi())))
 );

Parameters:: numbers - the numbers to calculate the sum for
Returns:: expression
See Also:: Style specification

sum

public static Expression sum(Number... numbers)

Returns the sum of the inputs.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(sum(10.0f, 5.0f, 3.0f)))
 );

Parameters:: numbers - the numbers to calculate the sum for
Returns:: expression
See Also:: Style specification

product

public static Expression product(Expression... numbers)

Returns the product of the inputs.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(product(literal(10.0f), ln2())))
 );

Parameters:: numbers - the numbers to calculate the product for
Returns:: expression
See Also:: Style specification

product

public static Expression product(Number... numbers)

Returns the product of the inputs.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(product(10.0f, 2.0f)))
 );

Parameters:: numbers - the numbers to calculate the product for
Returns:: expression
See Also:: Style specification

subtract

public static Expression subtract(Expression number)

Returns the result of subtracting a number from 0.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(subtract(pi()))
 );

Parameters:: number - the number subtract from 0
Returns:: expression
See Also:: Style specification

subtract

public static Expression subtract(Number number)

Returns the result of subtracting a number from 0.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(subtract(10.0f))
 );

Parameters:: number - the number subtract from 0
Returns:: expression
See Also:: Style specification

subtract

public static Expression subtract(Expression first,
                                  Expression second)

Returns the result of subtracting the second input from the first.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(subtract(literal(10.0f), pi())))
 );

Parameters:: first - the first number; second - the second number
Returns:: expression
See Also:: Style specification

subtract

public static Expression subtract(Number first,
                                  Number second)

Returns the result of subtracting the second input from the first.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(subtract(10.0f, 20.0f)))
 );

Parameters:: first - the first number; second - the second number
Returns:: expression
See Also:: Style specification

division

public static Expression division(Expression first,
                                  Expression second)

Returns the result of floating point division of the first input by the second.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(division(literal(10.0f), pi())))
 );

Parameters:: first - the first number; second - the second number
Returns:: expression
See Also:: Style specification

division

public static Expression division(Number first,
                                  Number second)

Returns the result of floating point division of the first input by the second.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(division(10.0f, 20.0f)))
 );

Parameters:: first - the first number; second - the second number
Returns:: expression
See Also:: Style specification

mod

public static Expression mod(Expression first,
                             Expression second)

Returns the remainder after integer division of the first input by the second.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(mod(literal(10.0f), pi()))
 );

Parameters:: first - the first number; second - the second number
Returns:: expression
See Also:: Style specification

mod

public static Expression mod(Number first,
                             Number second)

Returns the remainder after integer division of the first input by the second.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(mod(10.0f, 10.0f))
 );

Parameters:: first - the first number; second - the second number
Returns:: expression
See Also:: Style specification

pow

public static Expression pow(Expression first,
                             Expression second)

Returns the result of raising the first input to the power specified by the second.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(pow(pi(), literal(2.0f))
 );

Parameters:: first - the first number; second - the second number
Returns:: expression
See Also:: Style specification

pow

public static Expression pow(Number first,
                             Number second)

Returns the result of raising the first input to the power specified by the second.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(pow(5.0f, 2.0f))
 );

Parameters:: first - the first number; second - the second number
Returns:: expression
See Also:: Style specification

sqrt

public static Expression sqrt(Expression number)

Returns the square root of the input

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(sqrt(pi()))
 );

Parameters:: number - the number to take the square root from
Returns:: expression
See Also:: Style specification

sqrt

public static Expression sqrt(Number number)

Returns the square root of the input

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(sqrt(25.0f))
 );

Parameters:: number - the number to take the square root from
Returns:: expression
See Also:: Style specification

log10

public static Expression log10(Expression number)

Returns the base-ten logarithm of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(log10(pi()))
 );

Parameters:: number - the number to take base-ten logarithm from
Returns:: expression
See Also:: Style specification

log10

public static Expression log10(Number number)

Returns the base-ten logarithm of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(log10(10))
 );

Parameters:: number - the number to take base-ten logarithm from
Returns:: expression
See Also:: Style specification

ln

public static Expression ln(Expression number)

Returns the natural logarithm of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(ln(pi()))
 );

Parameters:: number - the number to take natural logarithm from
Returns:: expression
See Also:: Style specification

ln

public static Expression ln(Number number)

Returns the natural logarithm of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(ln(10))
 );

Parameters:: number - the number to take natural logarithm from
Returns:: expression
See Also:: Style specification

log2

public static Expression log2(Expression number)

Returns the base-two logarithm of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(log2(pi()))
 );

Parameters:: number - the number to take base-two logarithm from
Returns:: expression
See Also:: Style specification

log2

public static Expression log2(Number number)

Returns the base-two logarithm of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(log2(2))
 );

Parameters:: number - the number to take base-two logarithm from
Returns:: expression
See Also:: Style specification

sin

public static Expression sin(Expression number)

Returns the sine of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(sin(pi()))
 );

Parameters:: number - the number to calculate the sine for
Returns:: expression
See Also:: Style specification

sin

public static Expression sin(Number number)

Returns the sine of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(sin(90.0f))
 );

Parameters:: number - the number to calculate the sine for
Returns:: expression
See Also:: Style specification

cos

public static Expression cos(Expression number)

Returns the cosine of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(cos(pi()))
 );

Parameters:: number - the number to calculate the cosine for
Returns:: expression
See Also:: Style specification

cos

public static Expression cos(Number number)

Returns the cosine of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(cos(0)))
 );

Parameters:: number - the number to calculate the cosine for
Returns:: expression
See Also:: Style specification

tan

public static Expression tan(Expression number)

Returns the tangent of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(tan(pi()))
 );

Parameters:: number - the number to calculate the tangent for
Returns:: expression
See Also:: Style specification

tan

public static Expression tan(Number number)

Returns the tangent of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(tan(45.0f))
 );

Parameters:: number - the number to calculate the tangent for
Returns:: expression
See Also:: Style specification

asin

public static Expression asin(Expression number)

Returns the arcsine of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(asin(pi()))
 );

Parameters:: number - the number to calculate the arcsine for
Returns:: expression
See Also:: Style specification

asin

public static Expression asin(Number number)

Returns the arcsine of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(asin(90))
 );

Parameters:: number - the number to calculate the arcsine for
Returns:: expression
See Also:: Style specification

acos

public static Expression acos(Expression number)

Returns the arccosine of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(acos(pi()))
 );

Parameters:: number - the number to calculate the arccosine for
Returns:: expression
See Also:: Style specification

acos

public static Expression acos(Number number)

Returns the arccosine of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(acos(0))
 );

Parameters:: number - the number to calculate the arccosine for
Returns:: expression
See Also:: Style specification

atan

public static Expression atan(Expression number)

Returns the arctangent of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(asin(pi()))
 );

Parameters:: number - the number to calculate the arctangent for
Returns:: expression
See Also:: Style specification

atan

public static Expression atan(Number number)

Returns the arctangent of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(atan(90))
 );

Parameters:: number - the number to calculate the arctangent for
Returns:: expression
See Also:: Style specification

min

public static Expression min(Expression... numbers)

Returns the minimum value of the inputs.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(min(pi(), literal(3.14f), literal(3.15f))
 );

Parameters:: numbers - varargs of numbers to get the minimum from
Returns:: expression
See Also:: Style specification

min

public static Expression min(Number... numbers)

Returns the minimum value of the inputs.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(min(3.141, 3.14f, 3.15f))
 );

Parameters:: numbers - varargs of numbers to get the minimum from
Returns:: expression
See Also:: Style specification

max

public static Expression max(Expression... numbers)

Returns the maximum value of the inputs.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(max(pi(), 3.14f, 3.15f))
 );

Parameters:: numbers - varargs of numbers to get the maximum from
Returns:: expression
See Also:: Style specification

max

public static Expression max(Number... numbers)

Returns the maximum value of the inputs.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(max(3.141, 3.14f, 3.15f))
 );

Parameters:: numbers - varargs of numbers to get the maximum from
Returns:: expression
See Also:: Style specification

round
```
public static Expression round(Expression expression)
```
Rounds the input to the nearest integer. Halfway values are rounded away from zero. For example `[\"round\", -1.5]` evaluates to -2.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(round(pi()))
 );
 
 
```
Parameters:

expression - number expression to round

Returns:

expression

See Also:

Style specification

round
```
public static Expression round(Number number)
```
Rounds the input to the nearest integer. Halfway values are rounded away from zero. For example `[\"round\", -1.5]` evaluates to -2.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(round(3.14159265359f))
 );
 
 
```
Parameters:

number - number to round

Returns:

expression

See Also:

Style specification

abs

public static Expression abs(Expression expression)

Returns the absolute value of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(abs(subtract(pi())))
 );

Parameters:: expression - number expression to get absolute value from
Returns:: expression
See Also:: Style specification

abs

public static Expression abs(Number number)

Returns the absolute value of the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(abs(-3.14159265359f))
 );

Parameters:: number - number to get absolute value from
Returns:: expression
See Also:: Style specification

ceil

public static Expression ceil(Expression expression)

Returns the smallest integer that is greater than or equal to the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(ceil(pi()))
 );

Parameters:: expression - number expression to get value from
Returns:: expression
See Also:: Style specification

ceil

public static Expression ceil(Number number)

Returns the smallest integer that is greater than or equal to the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(ceil(3.14159265359))
 );

Parameters:: number - number to get value from
Returns:: expression
See Also:: Style specification

floor

public static Expression floor(Expression expression)

Returns the largest integer that is less than or equal to the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(floor(pi()))
 );

Parameters:: expression - number expression to get value from
Returns:: expression
See Also:: Style specification

floor

public static Expression floor(Number number)

Returns the largest integer that is less than or equal to the input.

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(floor(pi()))
 );

Parameters:: number - number to get value from
Returns:: expression
See Also:: Style specification

upcase
```
public static Expression upcase(Expression string)
```
Returns the input string converted to uppercase.
Follows the Unicode Default Case Conversion algorithm and the locale-insensitive case mappings in the Unicode Character Database.

Example usage:
```
 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(upcase(get("key-to-string-value"))
 );
 
 
```
Parameters:

string - the string to upcase

Returns:

expression

See Also:

Style specification

upcase
```
public static Expression upcase(String string)
```
Returns the input string converted to uppercase.
Follows the Unicode Default Case Conversion algorithm and the locale-insensitive case mappings in the Unicode Character Database.

Example usage:
```
 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(upcase("text"))
 );
 
 
```
Parameters:

string - string to upcase

Returns:

expression

See Also:

Style specification

downcase
```
public static Expression downcase(Expression input)
```
Returns the input string converted to lowercase.
Follows the Unicode Default Case Conversion algorithm and the locale-insensitive case mappings in the Unicode Character Database.

Example usage:
```
 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(downcase(get("key-to-string-value"))
 );
 
 
```
Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

downcase
```
public static Expression downcase(String input)
```
Returns the input string converted to lowercase.
Follows the Unicode Default Case Conversion algorithm and the locale-insensitive case mappings in the Unicode Character Database.

Example usage:
```
 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(upcase("key-to-string-value")
 );
 
 
```
Parameters:

input - string to downcase

Returns:

expression

See Also:

Style specification

concat

public static Expression concat(Expression... input)

Returns a string consisting of the concatenation of the inputs.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(concat(get("key-to-string-value"), literal("other string"))
 );

Parameters:: input - expression input
Returns:: expression
See Also:: Style specification

concat

public static Expression concat(String... input)

Returns a string consisting of the concatenation of the inputs.

Example usage:

 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(concat("foo", "bar"))
 );

Parameters:: input - expression input
Returns:: expression
See Also:: Style specification

array
```
public static Expression array(Expression input)
```
Asserts that the input is an array (optionally with a specific item type and length). If, when the input expression is evaluated, it is not of the asserted type, then this assertion will cause the whole expression to be aborted.

Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

typeOf
```
public static Expression typeOf(Expression input)
```
Returns a string describing the type of the given value.

Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

string
```
public static Expression string(Expression... input)
```
Asserts that the input value is a string. If multiple values are provided, each one is evaluated in order until a string value is obtained. If none of the inputs are strings, the expression is an error. The asserted input value is returned as result.

Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

number
```
public static Expression number(Expression... input)
```
Asserts that the input value is a number. If multiple values are provided, each one is evaluated in order until a number value is obtained. If none of the inputs are numbers, the expression is an error. The asserted input value is returned as result.

Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

bool
```
public static Expression bool(Expression... input)
```
Asserts that the input value is a boolean. If multiple values are provided, each one is evaluated in order until a boolean value is obtained. If none of the inputs are booleans, the expression is an error. The asserted input value is returned as result.

Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

object
```
public static Expression object(Expression input)
```
Asserts that the input value is an object. If it is not, the expression is an error The asserted input value is returned as result.

Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

toString
```
public static Expression toString(Expression input)
```
Converts the input value to a string. If the input is null, the result is null. If the input is a boolean, the result is true or false. If the input is a number, it is converted to a string by NumberToString in the ECMAScript Language Specification. If the input is a color, it is converted to a string of the form "rgba(r,g,b,a)", where `r`, `g`, and `b` are numerals ranging from 0 to 255, and `a` ranges from 0 to 1. Otherwise, the input is converted to a string in the format specified by the JSON.stringify in the ECMAScript Language Specification.
Example usage:
```
 
 SymbolLayer symbolLayer = new SymbolLayer("layer-id", "source-id");
 symbolLayer.setProperties(
     textField(toString(get("key-to-number-value")))
 );
 
 
```
Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

toNumber
```
public static Expression toNumber(Expression input)
```
Converts the input value to a number, if possible. If the input is null or false, the result is 0. If the input is true, the result is 1. If the input is a string, it is converted to a number as specified by the ECMAScript Language Specification. If multiple values are provided, each one is evaluated in order until the first successful conversion is obtained. If none of the inputs can be converted, the expression is an error.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(toNumber(get("key-to-string-value")))
 );
 
 
```
Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

toBool
```
public static Expression toBool(Expression input)
```
Converts the input value to a boolean. The result is `false` when then input is an empty string, 0, false, null, or NaN; otherwise it is true.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(toBool(get("key-to-value"));
 );
 
 
```
Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

toColor
```
public static Expression toColor(Expression input)
```
Converts the input value to a color. If multiple values are provided, each one is evaluated in order until the first successful conversion is obtained. If none of the inputs can be converted, the expression is an error.
Example usage:
```
 
 FillLayer fillLayer = new FillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(toColor(get("keyStringValue")))
 );
 
 
```
Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

let
```
public static Expression let(Expression... input)
```
Binds input to named variables, which can then be referenced in the result expression using var(String) or var(Expression).

Parameters:

input - expression input

Returns:

expression

See Also:

Style specification

var
```
public static Expression var(Expression expression)
```
References variable bound using let.

Parameters:

expression - the variable naming expression that was bound with using let

Returns:

expression

See Also:

Style specification

var
```
public static Expression var(String variableName)
```
References variable bound using let.

Parameters:

variableName - the variable naming that was bound with using let

Returns:

expression

See Also:

Style specification

zoom

public static Expression zoom()

Gets the current zoom level.

Note that in style layout and paint properties, zoom may only appear as the input to a top-level step or interpolate expression.

Example usage:

 
 FillLayer fillLayer = new fillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
       interpolate(
         exponential(0.5f), zoom(),
         literal(1.0f), color(Color.RED),
         literal(5.0f, color(Color.BLUE),
         literal(10.0f, color(Color.GREEN)
       )
     )
 );

Returns:: expression
See Also:: Style specification

stop

public static Expression.Stop stop(Object stop,
                                   Object value)

Produces a stop value.

Can be used for stop(Object, Object) as part of varargs parameter in step(Number, Expression, Stop...) or interpolate(Interpolator, Expression, Stop...).

Example usage:

 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(
         step(zoom(), literal(0.0f),
         stop(1.0f, 2.5f),
         stop(10.0f, 5.0f)
     )
 );

Parameters:: stop - the stop input; value - the stop output
Returns:: the stop

step
```
public static Expression step(Number input,
                              Expression defaultOutput,
                              Expression... stops)
```
Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\"). The `input` may be any numeric expression (e.g., `[\"get\", \"population\"]`). Stop inputs must be numeric literals in strictly ascending order. Returns the output value of the stop just less than the input, or the first input if the input is less than the first stop.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(
         step(zoom(), literal(0.0f),
         literal(1.0f), literal(2.5f),
         literal(10.0f), literal(5.0f)
     )
 );
 
 
```
Parameters:

input - the input value

defaultOutput - the default output expression

stops - pair of input and output values

Returns:

expression

See Also:

Style specification

step
```
public static Expression step(Expression input,
                              Expression defaultOutput,
                              Expression... stops)
```
Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\"). The `input` may be any numeric expression (e.g., `[\"get\", \"population\"]`). Stop inputs must be numeric literals in strictly ascending order. Returns the output value of the stop just less than the input, or the first input if the input is less than the first stop.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(
         step(zoom(), literal(0.0f),
         literal(1.0f), literal(2.5f),
         literal(10.0f), literal(5.0f)
     )
 );
 
 
```
Parameters:

input - the input expression

defaultOutput - the default output expression

stops - pair of input and output values

Returns:

expression

See Also:

Style specification

step
```
public static Expression step(Number input,
                              Expression defaultOutput,
                              Expression.Stop... stops)
```
Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\"). The `input` may be any numeric expression (e.g., `[\"get\", \"population\"]`). Stop inputs must be numeric literals in strictly ascending order. Returns the output value of the stop just less than the input, or the first input if the input is less than the first stop.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(
         step(zoom(), literal(0.0f),
         stop(1, 2.5f),
         stop(10, 5.0f)
     )
 );
 
 
```
Parameters:

input - the input value

defaultOutput - the default output expression

stops - pair of input and output values

Returns:

expression

See Also:

Style specification

step
```
public static Expression step(Expression input,
                              Expression defaultOutput,
                              Expression.Stop... stops)
```
Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\"). The `input` may be any numeric expression (e.g., `[\"get\", \"population\"]`). Stop inputs must be numeric literals in strictly ascending order. Returns the output value of the stop just less than the input, or the first input if the input is less than the first stop.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(
         step(zoom(), literal(0.0f),
         stop(1, 2.5f),
         stop(10, 5.0f)
     )
 );
 
 
```
Parameters:

input - the input value

defaultOutput - the default output expression

stops - pair of input and output values

Returns:

expression

See Also:

Style specification

step
```
public static Expression step(Number input,
                              Number defaultOutput,
                              Expression... stops)
```
Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\"). The `input` may be any numeric expression (e.g., `[\"get\", \"population\"]`). Stop inputs must be numeric literals in strictly ascending order. Returns the output value of the stop just less than the input, or the first input if the input is less than the first stop.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(
         step(1.0f, 0.0f,
         literal(1.0f), literal(2.5f),
         literal(10.0f), literal(5.0f)
     )
 );
 
 
```
Parameters:

input - the input value

defaultOutput - the default output expression

stops - pair of input and output values

Returns:

expression

See Also:

Style specification

step
```
public static Expression step(Expression input,
                              Number defaultOutput,
                              Expression... stops)
```
Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\"). The `input` may be any numeric expression (e.g., `[\"get\", \"population\"]`). Stop inputs must be numeric literals in strictly ascending order. Returns the output value of the stop just less than the input, or the first input if the input is less than the first stop.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(
         step(zoom(), 0.0f,
         literal(1.0f), literal(2.5f),
         literal(10.0f), literal(5.0f)
     )
 );
 
 
```
Parameters:

input - the input expression

defaultOutput - the default output expression

stops - pair of input and output values

Returns:

expression

See Also:

Style specification

step
```
public static Expression step(Number input,
                              Number defaultOutput,
                              Expression.Stop... stops)
```
Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\"). The `input` may be any numeric expression (e.g., `[\"get\", \"population\"]`). Stop inputs must be numeric literals in strictly ascending order. Returns the output value of the stop just less than the input, or the first input if the input is less than the first stop.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(
         step(zoom(), 0.0f,
         stop(1, 2.5f),
         stop(10, 5.0f)
     )
 );
 
 
```
Parameters:

input - the input value

defaultOutput - the default output expression

stops - pair of input and output values

Returns:

expression

See Also:

Style specification

step
```
public static Expression step(Expression input,
                              Number defaultOutput,
                              Expression.Stop... stops)
```
Produces discrete, stepped results by evaluating a piecewise-constant function defined by pairs of input and output values (\"stops\"). The `input` may be any numeric expression (e.g., `[\"get\", \"population\"]`). Stop inputs must be numeric literals in strictly ascending order. Returns the output value of the stop just less than the input, or the first input if the input is less than the first stop.
Example usage:
```
 
 CircleLayer circleLayer = new CircleLayer("layer-id", "source-id");
 circleLayer.setProperties(
     circleRadius(
         step(zoom(), 0.0f,
         stop(1, 2.5f),
         stop(10, 5.0f)
     )
 );
 
 
```
Parameters:

input - the input value

defaultOutput - the default output expression

stops - pair of input and output values

Returns:

expression

See Also:

Style specification

interpolate

public static Expression interpolate(Expression.Interpolator interpolation,
                                     Expression number,
                                     Expression... stops)

Produces continuous, smooth results by interpolating between pairs of input and output values (\"stops\"). The `input` may be any numeric expression (e.g., `[\"get\", \"population\"]`). Stop inputs must be numeric literals in strictly ascending order. The output type must be `number`, `array<number>`, or `color`.

Example usage:

 
 FillLayer fillLayer = new fillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
       interpolate(
         exponential(0.5f), zoom(),
         literal(1.0f), color(Color.RED),
         literal(5.0f, color(Color.BLUE),
         literal(10.0f, color(Color.GREEN)
       )
     )
 );

Parameters:: interpolation - type of interpolation; number - the input expression; stops - pair of input and output values
Returns:: expression
See Also:: Style specification

interpolate

public static Expression interpolate(Expression.Interpolator interpolation,
                                     Expression number,
                                     Expression.Stop... stops)

Example usage:

 
 FillLayer fillLayer = new fillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
       interpolate(
         exponential(0.5f), zoom(),
         literal(1.0f), color(Color.RED),
         literal(5.0f, color(Color.BLUE),
         literal(10.0f, color(Color.GREEN)
       )
     )
 );

Parameters:: interpolation - type of interpolation; number - the input expression; stops - pair of input and output values
Returns:: expression
See Also:: Style specification

linear

public static Expression.Interpolator linear()

interpolates linearly between the pair of stops just less than and just greater than the input.

Example usage:

 
 FillLayer fillLayer = new fillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
       interpolate(
         linear(), zoom(),
         literal(1.0f), color(Color.RED),
         literal(5.0f, color(Color.BLUE),
         literal(10.0f, color(Color.GREEN)
       )
     )
 );

Returns:: expression
See Also:: Style specification

exponential
```
public static Expression.Interpolator exponential(Number base)
```
Interpolates exponentially between the stops just less than and just greater than the input. `base` controls the rate at which the output increases: higher values make the output increase more towards the high end of the range. With values close to 1 the output increases linearly.
Example usage:
```
 
 FillLayer fillLayer = new fillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
       interpolate(
         exponential(0.5f), zoom(),
         literal(1.0f), color(Color.RED),
         literal(5.0f, color(Color.BLUE),
         literal(10.0f, color(Color.GREEN)
       )
     )
 );
 
 
```
Parameters:

base - value controlling the route at which the output increases

Returns:

expression

See Also:

Style specification

exponential

public static Expression.Interpolator exponential(Expression expression)

Interpolates exponentially between the stops just less than and just greater than the input. The parameter controls the rate at which the output increases: higher values make the output increase more towards the high end of the range. With values close to 1 the output increases linearly.

Example usage:

 
 FillLayer fillLayer = new fillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
       interpolate(
         exponential(get("keyToValue"), zoom(),
         literal(1.0f), color(Color.RED),
         literal(5.0f, color(Color.BLUE),
         literal(10.0f, color(Color.GREEN)
       )
     )
 );

Parameters:: expression - base number expression
Returns:: expression
See Also:: Style specification

cubicBezier

public static Expression.Interpolator cubicBezier(Expression x1,
                                                  Expression y1,
                                                  Expression x2,
                                                  Expression y2)

Interpolates using the cubic bezier curve defined by the given control points.

Example usage:

 
 FillLayer fillLayer = new fillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
       interpolate(
         cubicBezier(0.42f, 0.0f, 1.0f, 1.0f), zoom(),
         literal(1.0f), color(Color.RED),
         literal(5.0f, color(Color.BLUE),
         literal(10.0f, color(Color.GREEN)
       )
     )
 );

Parameters:: x1 - x value of the first point of a cubic bezier, ranges from 0 to 1; y1 - y value of the first point of a cubic bezier, ranges from 0 to 1; x2 - x value of the second point of a cubic bezier, ranges from 0 to 1; y2 - y value fo the second point of a cubic bezier, ranges from 0 to 1
Returns:: expression
See Also:: Style specification

cubicBezier

public static Expression.Interpolator cubicBezier(Number x1,
                                                  Number y1,
                                                  Number x2,
                                                  Number y2)

Interpolates using the cubic bezier curve defined by the given control points.

Example usage:

 
 FillLayer fillLayer = new fillLayer("layer-id", "source-id");
 fillLayer.setProperties(
     fillColor(
       interpolate(
         cubicBezier(0.42f, 0.0f, 1.0f, 1.0f), zoom(),
         literal(1.0f), color(Color.RED),
         literal(5.0f, color(Color.BLUE),
         literal(10.0f, color(Color.GREEN)
       )
     )
 );

Parameters:: x1 - x value of the first point of a cubic bezier, ranges from 0 to 1; y1 - y value of the first point of a cubic bezier, ranges from 0 to 1; x2 - x value of the second point of a cubic bezier, ranges from 0 to 1; y2 - y value fo the second point of a cubic bezier, ranges from 0 to 1
Returns:: expression
See Also:: Style specification

toArray
```
public Object[] toArray()
```
Converts the expression to Object array representation.
The output will later be converted to a JSON Object array.

Returns:

the converted object array expression

toString
```
public String toString()
```
Returns a string representation of the object that matches the definition set in the style specification.
If this expression contains a coma (,) delimited literal, like 'rgba(r, g, b, a)`, it will be enclosed with double quotes (").

Overrides:

toString in class Object

Returns:

a string representation of the object.

raw
```
public static Expression raw(String rawExpression)
```
Returns a DSL equivalent of a raw expression.
If your raw expression contains a coma (,) delimited literal it has to be enclosed with double quotes ("), for example
```
   
   ["to-color", "rgba(255, 0, 0, 255)"]
   
 
```
Parameters:

rawExpression - the raw expression

Returns:

the resulting expression

See Also:

Style specification

equals
```
public boolean equals(Object o)
```
Indicates whether some other object is "equal to" this one.

Overrides:

equals in class Object

Parameters:

o - the other object

Returns:

true if equal, false if not

hashCode
```
public int hashCode()
```
Returns a hash code value for the expression.

Overrides:

hashCode in class Object

Returns:

a hash code value for this expression

Class Expression

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Expression

Method Detail

literal

literal

literal

literal

literal

color

rgb

rgb

rgba

rgba

toRgba

eq

eq

eq

eq

neq

neq

neq

neq

gt

gt

gt

lt

lt

lt

gte

gte

gte

lte

lte

lte

all

any

not

not

switchCase

match

match

coalesce

properties

geometryType

id

heatmapDensity

at

at

get

get

get

get

has

has

has

has

length

length

ln2

pi

e

sum

sum

product

product

subtract

subtract

subtract

subtract

division

division

mod

mod

pow

pow