TMtxExpression.DefineVector Method (string, TVec)

Defines new vector variable.

Pascal

function DefineVector(const AVarName: string; const Vec: TVec): TVectorValue; overload;

If variable with name AVarName already was definded, it is redefined and all expressions which contain the symbol AVarName will be recompiled before the next evaluation. External vector may be assigned as values holder. If external vector is not assigned, internal vector will be used.

Example

Use parser to evaluate the "-s*x" formula where x(1,-1,1) is vector and s=0.5 scalar. To evaluate vector, use automatically generated vector.

uses MtxParseExpr, MtxExpr, MtxParseClass; procedure Example(MyParser: TMtxExpression); var x: TVectorValue; s: TDoubleValue; res: Vector; begin // 1. Define variables x := MyParser.DefineVector('x'); s := MyParser.DefineDouble('s'); // 2. Set values x.Value.SetIt(false,[1,-1,1]); s.DoubleValue := 0.5; // 3. Add formula and evaluate, MyParser.AddExpr('-s*x'); res := MyParser.EvaluateVector; // res = (-0.5,0.5, -0.5) end;

TMtxExpression Class, TMtxExpression Members, MtxParseExpr Namespace, DefineVector Method, Example, See Also

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