TMtxExpression.DefineMatrix Method (string, TMtx)

DefineMatrix defines new matrix variable.

Pascal

function DefineMatrix(const AVarName: string; const mtx: TMtx): TMatrixValue; overload;

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

Example

Use parser to evaluate the "A+2*B" formula where A=(2,1; 3, 0) B=(1,0; 1,1) are 2x2 matrices.

uses MtxParseExpr, MtxExpr, MtxParseClass; procedure Example(MyParser: TMtxExpression); var A,B: TMatrixValue; res: Matrix; begin // 1. Define variables A := MyParser.DefineMatrix('A'); B := MyParser.DefineDouble('B'); // 2. Set values A.Value.SetIt(2,2, false, [2,1,3,0]); B.Value.SetIt(2,2, false, [1,0,1,1]); // 3. Add formula and evaluate, MyParser.AddExpr('A+2*B'); res := MyParser.EvaluateMatrix; // res = (4,1; 5,2) end;

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

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