TMtxExpression::DefineDouble Method

TDoubleValue *DefineDouble(const DewString &AVarName);

Defines new double variable.

#	Name	Type	Description
1	AVarName	const DewString &

Remarks:

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.

Examples

#include "MtxParseClass.h"
#include "MtxParseExpr.h"

using namespace Dew;
using namespace Dew::Math;

void Example()
{
    TMtxExpression* MyParser = new TMtxExpression();
    // 1. Define variables
    TDoubleValue* x = MyParser->DefineDouble("x");
    TDoubleValue* y = MyParser->DefineDouble("y");

    // 2. Set values
    x->DoubleValue = 3.0;
    y->DoubleValue = 4.0;

    // 3. Add formula and evaluate,
    MyParser->AddExpr("Sqrt(x*x+y*y)");
    double res = MyParser->EvaluateDouble();
    // res = 5
    delete MyParser;
}

See Also: TMtxExpression::Undefine, TMtxExpression::VarByName, TMtxExpression::GetVarList, TMtxExpression::DefineVariable, TMtxExpression::DefineComplex, TMtxExpression::DefineVector, TMtxExpression::DefineMatrix, TMtxExpression::DefineFunction, TMtxExpression::DefineVaryingFunction, TMtxExpression::DefineOperator, TMtxExpression::DefineDoubleConstant, TMtxExpression::DefineComplexConstant

Declared in Dew::Math::TMtxExpression · Dew.Math/MtxParseExpr.h · Cross-compiler