OakGP Functions

Functions

Below is a list of functions that OakGP provides. You can define your own functions by implementing org.oakgp.function.Function.

org.oakgp.function.choice - Provides functions for selection.
   org.oakgp.function.choice.If - A selection operator that uses a boolean expression to determine which code to evaluate.
   org.oakgp.function.choice.OrElse - Returns the first argument if not null, else returns the second argument.
   org.oakgp.function.choice.SwitchEnum - A selection operator that uses the value of an enum to determine which code to evaluate.

org.oakgp.function.classify - Provides functions for classifying Node instances.
   org.oakgp.function.classify.IsNegative - Determines if a number is negative.
   org.oakgp.function.classify.IsPositive - Determines if a number is positive.
   org.oakgp.function.classify.IsZero - Determines if a number is zero.

org.oakgp.function.coll - Provides functions for working with collections.
   org.oakgp.function.coll.Count - Determines the number of elements contained in a collection.

org.oakgp.function.compare - Provides functions for comparing the results of evaluating Node instances.
   org.oakgp.function.compare.NotEqual - Determines if two objects are not equal.
   org.oakgp.function.compare.LessThan - Determines if the object represented by the first argument is less than the object represented by the second.
   org.oakgp.function.compare.LessThanOrEqual - Determines if the object represented by the first argument is less than or equal to the object represented by the second.
   org.oakgp.function.compare.Equal - Determines if two objects are equal.
   org.oakgp.function.compare.GreaterThan - Determines if the object represented by the first argument is greater than the object represented by the second.
   org.oakgp.function.compare.GreaterThanOrEqual - Determines if the object represented by the first argument is greater than or equal to the object represented by the second.

org.oakgp.function.hof - Provides higher-order functions.
   org.oakgp.function.hof.Filter - Uses a function to filter the elements of a collection.
   org.oakgp.function.hof.Map - Returns the result of applying a function to each element of a collection.
   org.oakgp.function.hof.Reduce - Combines the elements of a collection by recursively applying a function.

org.oakgp.function.math - Provides operations for performing arithmetic.
   org.oakgp.function.math.Multiply - Performs multiplication.
   org.oakgp.function.math.Add - Performs addition.
   org.oakgp.function.math.Subtract - Performs subtraction.
   org.oakgp.function.math.Divide - Performs division.

Package:	`org.oakgp.function.choice`
Description:	Provides functions for selection.

Function: if

Class: org.oakgp.function.choice.If

Description:

A selection operator that uses a boolean expression to determine which code to evaluate.

Expects three arguments:

Conditional statement.
Value to evaluate to if the conditional statement is true.
Value to evaluate to if the conditional statement is false.

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Function:	`orelse`
Class:	`org.oakgp.function.choice.OrElse`
Description:	Returns the first argument if not `null`, else returns the second argument.

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Function:	`switch`
Class:	`org.oakgp.function.choice.SwitchEnum`
Description:	A selection operator that uses the value of an enum to determine which code to evaluate. This behaviour is similar to a Java `switch` statement that uses an enum.

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Package:	`org.oakgp.function.classify`
Description:	Provides functions for classifying `Node` instances.

Function:	`neg?`
Class:	`org.oakgp.function.classify.IsNegative`
Description:	Determines if a number is negative.

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Function:	`pos?`
Class:	`org.oakgp.function.classify.IsPositive`
Description:	Determines if a number is positive.

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Function:	`zero?`
Class:	`org.oakgp.function.classify.IsZero`
Description:	Determines if a number is zero.

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Package:	`org.oakgp.function.coll`
Description:	Provides functions for working with collections.

Function:	`count`
Class:	`org.oakgp.function.coll.Count`
Description:	Determines the number of elements contained in a collection.

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Package:	`org.oakgp.function.compare`
Description:	Provides functions for comparing the results of evaluating `Node` instances.

Function:	`!=`
Class:	`org.oakgp.function.compare.NotEqual`
Description:	Determines if two objects are not equal. Note: Equality is checked using `Comparable#compareTo(Object)` rather than `Object#equals(Object)`.

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Function:	`<`
Class:	`org.oakgp.function.compare.LessThan`
Description:	Determines if the object represented by the first argument is less than the object represented by the second.

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Function:	`<=`
Class:	`org.oakgp.function.compare.LessThanOrEqual`
Description:	Determines if the object represented by the first argument is less than or equal to the object represented by the second.

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Function:	`=`
Class:	`org.oakgp.function.compare.Equal`
Description:	Determines if two objects are equal. Note: Equality is checked using `Comparable#compareTo(Object)` rather than `Object#equals(Object)`.

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Function:	`>`
Class:	`org.oakgp.function.compare.GreaterThan`
Description:	Determines if the object represented by the first argument is greater than the object represented by the second.

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Function:	`>=`
Class:	`org.oakgp.function.compare.GreaterThanOrEqual`
Description:	Determines if the object represented by the first argument is greater than or equal to the object represented by the second.

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Package: org.oakgp.function.hof

Description:

Provides higher-order functions.

A higher-order function is a function that does at least one of the following:

Takes one or more functions as input.
Returns a function.

See: Wikipedia

Function:	`filter`
Class:	`org.oakgp.function.hof.Filter`
Description:	Uses a function to filter the elements of a collection. Returns a new collection that exists of all the elements in the collection (specified by the second argument) for which the function (specified by the first argument) returns `true`. See: Wikipedia

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Function:	`map`
Class:	`org.oakgp.function.hof.Map`
Description:	Returns the result of applying a function to each element of a collection. Returns a new collection that exists of the result of applying the function (specified by the first argument) to each element of the collection (specified by the second argument). See: Wikipedia

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Function: reduce

Class: org.oakgp.function.hof.Reduce

Description:

Combines the elements of a collection by recursively applying a function.

Expects three arguments:

A function.
An initial value.
A collection.

See: Wikipedia

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Package:	`org.oakgp.function.math`
Description:	Provides operations for performing arithmetic.

Function:	`*`
Class:	`org.oakgp.function.math.Multiply`
Description:	Performs multiplication.

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Function:	`+`
Class:	`org.oakgp.function.math.Add`
Description:	Performs addition.

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Input expression:

(+ 3 21)

Signature:

Returns:	`integer`
Arguments:	`integer integer`

Output:

Value:	`24`
Class:	`java.lang.Integer`

Input expression:

(+ 2147483647 1)

Signature:

Returns:	`integer`
Arguments:	`integer integer`

Output:

Value:	`-2147483648`
Class:	`java.lang.Integer`

Input expression:

(+ 3L 21L)

Signature:

Returns:	`long`
Arguments:	`long long`

Output:

Value:	`24`
Class:	`java.lang.Long`

Input expression:

(+ 2147483647L 1L)

Signature:

Returns:	`long`
Arguments:	`long long`

Output:

Value:	`2147483648`
Class:	`java.lang.Long`

Input expression:

(+ 9223372036854775807L 1L)

Signature:

Returns:	`long`
Arguments:	`long long`

Output:

Value:	`-9223372036854775808`
Class:	`java.lang.Long`

Input expression:

(+ 3I 21I)

Signature:

Returns:	`BigInteger`
Arguments:	`BigInteger BigInteger`

Output:

Value:	`24`
Class:	`java.math.BigInteger`

Input expression:

(+ 2147483647I 1I)

Signature:

Returns:	`BigInteger`
Arguments:	`BigInteger BigInteger`

Output:

Value:	`2147483648`
Class:	`java.math.BigInteger`

Input expression:

(+ 9223372036854775807I 1I)

Signature:

Returns:	`BigInteger`
Arguments:	`BigInteger BigInteger`

Output:

Value:	`9223372036854775808`
Class:	`java.math.BigInteger`

Input expression:

(+ 3.0 21.0)

Signature:

Returns:	`double`
Arguments:	`double double`

Output:

Value:	`24.0`
Class:	`java.lang.Double`

Input expression:

(+ 7.5 -0.025)

Signature:

Returns:	`double`
Arguments:	`double double`

Output:

Value:	`7.475`
Class:	`java.lang.Double`

Input expression:

(+ 5.6 5.8)

Signature:

Returns:	`double`
Arguments:	`double double`

Output:

Value:	`11.399999999999999`
Class:	`java.lang.Double`

Input expression:

(+ 2.147483647E9 1.0)

Signature:

Returns:	`double`
Arguments:	`double double`

Output:

Value:	`2.147483648E9`
Class:	`java.lang.Double`

Input expression:

(+ 9.223372036854776E18 1.0)

Signature:

Returns:	`double`
Arguments:	`double double`

Output:

Value:	`9.223372036854776E18`
Class:	`java.lang.Double`

Input expression:

(+ 1.7976931348623157E308 1.0)

Signature:

Returns:	`double`
Arguments:	`double double`

Output:

Value:	`1.7976931348623157E308`
Class:	`java.lang.Double`

Input expression:

(+ 3D 21D)

Signature:

Returns:	`BigDecimal`
Arguments:	`BigDecimal BigDecimal`

Output:

Value:	`24`
Class:	`java.math.BigDecimal`

Input expression:

(+ 7.5D -0.025D)

Signature:

Returns:	`BigDecimal`
Arguments:	`BigDecimal BigDecimal`

Output:

Value:	`7.475`
Class:	`java.math.BigDecimal`

Input expression:

(+ 5.6D 5.8D)

Signature:

Returns:	`BigDecimal`
Arguments:	`BigDecimal BigDecimal`

Output:

Value:	`11.4`
Class:	`java.math.BigDecimal`

Input expression:

(+ 2147483647D 1D)

Signature:

Returns:	`BigDecimal`
Arguments:	`BigDecimal BigDecimal`

Output:

Value:	`2147483648`
Class:	`java.math.BigDecimal`

Input expression:

(+ 9223372036854775807D 1D)

Signature:

Returns:	`BigDecimal`
Arguments:	`BigDecimal BigDecimal`

Output:

Value:	`9223372036854775808`
Class:	`java.math.BigDecimal`

Input expression:

(+ 1.7976931348623157E+308D 1D)

Signature:

Returns:	`BigDecimal`
Arguments:	`BigDecimal BigDecimal`

Output:

Value:	`179769313486231570000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001`
Class:	`java.math.BigDecimal`

Function:	`-`
Class:	`org.oakgp.function.math.Subtract`
Description:	Performs subtraction.

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Function:	`/`
Class:	`org.oakgp.function.math.Divide`
Description:	Performs division.

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Input expression:

(/ 21 3)

Signature:

Returns:	`integer`
Arguments:	`integer integer`

Output:

Value:	`7`
Class:	`java.lang.Integer`

Input expression:

(/ 5 2)

Signature:

Returns:	`integer`
Arguments:	`integer integer`

Output:

Value:	`2`
Class:	`java.lang.Integer`

Input expression:

(/ 12 1)

Signature:

Returns:	`integer`
Arguments:	`integer integer`

Output:

Value:	`12`
Class:	`java.lang.Integer`

Input expression:

(/ 12 12)

Signature:

Returns:	`integer`
Arguments:	`integer integer`

Output:

Value:	`1`
Class:	`java.lang.Integer`

Input expression:

(/ 21L 3L)

Signature:

Returns:	`long`
Arguments:	`long long`

Output:

Value:	`7`
Class:	`java.lang.Long`

Input expression:

(/ 5L 2L)

Signature:

Returns:	`long`
Arguments:	`long long`

Output:

Value:	`2`
Class:	`java.lang.Long`

Input expression:

(/ 21I 3I)

Signature:

Returns:	`BigInteger`
Arguments:	`BigInteger BigInteger`

Output:

Value:	`7`
Class:	`java.math.BigInteger`

Input expression:

(/ 5I 2I)

Signature:

Returns:	`BigInteger`
Arguments:	`BigInteger BigInteger`

Output:

Value:	`2`
Class:	`java.math.BigInteger`

Input expression:

(/ 21.0 3.0)

Signature:

Returns:	`double`
Arguments:	`double double`

Output:

Value:	`7.0`
Class:	`java.lang.Double`

Input expression:

(/ 5.0 2.0)

Signature:

Returns:	`double`
Arguments:	`double double`

Output:

Value:	`2.5`
Class:	`java.lang.Double`

Input expression:

(/ 21D 3D)

Signature:

Returns:	`BigDecimal`
Arguments:	`BigDecimal BigDecimal`

Output:

Value:	`7`
Class:	`java.math.BigDecimal`

Input expression:

(/ 5D 2D)

Signature:

Returns:	`BigDecimal`
Arguments:	`BigDecimal BigDecimal`

Output:

Value:	`2.5`
Class:	`java.math.BigDecimal`

Input expression:

(/ 12 0)

Signature:

Returns:	`integer`
Arguments:	`integer integer`

Output:

Value:	`1`
Class:	`java.lang.Integer`

Input expression:

(/ 12L 0L)

Signature:

Returns:	`long`
Arguments:	`long long`

Output:

Value:	`1`
Class:	`java.lang.Long`

Input expression:

(/ 12I 0I)

Signature:

Returns:	`BigInteger`
Arguments:	`BigInteger BigInteger`

Output:

Value:	`1`
Class:	`java.math.BigInteger`

Input expression:

(/ 12.0 0.0)

Signature:

Returns:	`double`
Arguments:	`double double`

Output:

Value:	`1.0`
Class:	`java.lang.Double`

Input expression:

(/ 12D 0D)

Signature:

Returns:	`BigDecimal`
Arguments:	`BigDecimal BigDecimal`

Output:

Value:	`1`
Class:	`java.math.BigDecimal`

v0:	`null`
v1:	java.lang.String with value: `default`

v0:	java.lang.String with value: `hello`
v1:	java.lang.String with value: `default`

Returns:	`array [integer]`
Arguments:	`function [boolean, integer] array [integer]`

Returns:	`array [boolean]`
Arguments:	`function [boolean, integer] array [integer]`

Value:	`[true, false, true, false, false, true]`
Class:	`org.oakgp.Arguments`

Value:	`[false, true, false, true, true, false]`
Class:	`org.oakgp.Arguments`

Value:	`[false, false, false, false, false, false]`
Class:	`org.oakgp.Arguments`

Returns:	`string`
Arguments:	`nullable [string] string`

Returns:	`string`
Arguments:	`nullable [string] string`

Returns:	`integer`
Arguments:	`nullable [exampleEnum] integer integer integer integer`

Returns:	`integer`
Arguments:	`nullable [exampleEnum] integer integer integer integer`