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MtxVec VCL
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TMtxExpression.VarByName Property
TMtxExpression Class | TMtxExpression Members | MtxParseExpr Namespace | public | Example | See Also
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Returns variable by name or nil, if variable does not exist.

Pascal
property VarByName: TVarByNameIndexer;
See Also
Example

Use parser to evaluate the "(2*i*z)" formula where z=-2+3*i.

uses MtxParseExpr, MtxParseClass; procedure Example(MyParser: TMtxExpression); var z: TValueRec; res: TCplx; begin // 1. Add formula, MyParser.AddExpr('2*i*z'); // 2. Get defined variables z := MyParser.VarByName['z']; // 3. Specify their type z.DefineComplex; // 4. Set values z.ComplexValue := Cplx(-2,3); // or z.ComplexValue := '-2 + 3i'; // 5. Evaluate res := MyParser.EvaluateComplex; // res = -6-4*i Caption := CplxToStr(res); end;
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