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- Overrides:
evaluate in class AbstractArg2- Parameters:
ast - the abstract syntax tree (AST) which should be evaluatedengine - 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()