org.matheclipse.core.reflection.system

Class Subsets

java.lang.Object

org.matheclipse.core.eval.interfaces.AbstractEvaluator

org.matheclipse.core.eval.interfaces.AbstractFunctionEvaluator

org.matheclipse.core.reflection.system.Subsets

All Implemented Interfaces:

IFunctionEvaluator, IEvaluator

public class Subsets
extends AbstractFunctionEvaluator

Generate a list of all k-combinations from a given list See Combination

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Subsets.KSubsetsIterable Iterable for all k-combinations from a set See Combination
static class	Subsets.KSubsetsList Iterate over the lists of all k-combinations from a given list See Combination

Constructor Summary

Constructors

Constructor and Description
Subsets()

Method Summary

Modifier and Type	Method and Description
static Subsets.KSubsetsList	createKSubsets(IAST list, int k, IAST resultList, int offset)
IExpr	evaluate(IAST ast, EvalEngine engine) Symbolic evaluation of a function.

Methods inherited from class org.matheclipse.core.eval.interfaces.AbstractFunctionEvaluator

createRuleFromMethod, getNormalizedNegativeExpression, getNormalizedNegativeExpression, getPeriodicParts, getPureImaginaryPart, getRuleAST, initSerializedRules, isNegativeExpression, setUp

Methods inherited from class org.matheclipse.core.eval.interfaces.AbstractEvaluator

numericEval

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Subsets

public Subsets()

Method Detail

evaluate

public IExpr evaluate(IAST ast,
                      EvalEngine engine)

Symbolic evaluation of a function. ast.get(0) (or alternatively ast.head()) contains the head (i.e. the function symbol) of this abstract syntax tree (AST).
From ast.arg1() to ast.get(n) the ast contains the first to n-th argument of the function (alternatively you get the first to fifth argument with the methods arg1(), arg2(),... arg5()).
If necessary use the methods from the Validate class to check the number or types of arguments in the evaluate method.
Note: if the symbolic evaluation isn't possible or no result is found the evaluate method returns with a null value without throwing an exception!

Specified by:

evaluate in interface IFunctionEvaluator

Specified by:

evaluate in class AbstractFunctionEvaluator

Parameters:

ast - the abstract syntax tree (AST) which should be evaluated

engine - the users current evaluation engine

Returns:

the evaluated object or null, if evaluation isn't possible

See Also:

Validate, IExpr.head(), IAST.arg1(), IAST.arg2(), IAST.arg3()

createKSubsets

public static Subsets.KSubsetsList createKSubsets(IAST list,
                                                  int k,
                                                  IAST resultList,
                                                  int offset)