EquTranslator 4.0.101

EquTranslator is fast and compact math parser/evaluator with pre-build feature and user-friendly interface. It uses recursive descent and operator precedence rules to parse and evaluate run-time defined strings as math expressions.

Valid math expressions should consist of :

• Variables should start from a letter and be no more than 32 characters long. The math expression may have unlimited number of variables.
• Arithmetic operations : +, -, *, / , ^ .
• Functions - set of predefined functions: : abs(x), acos(x), asin(x), atan(x), ceil(x), cos(x), cosh(x), exp(x), floor(x), J0(x), J1(x), ln(x), log10(x), sin(x), sinh(x), sqrt(x), tan(x), tanh(x), Y0(x), Y1(x). Also, users can define their own function to improve performance and extend functionality.

The main characteristics of EquTranslator :

• Extremely fast.
• Friendly interface and error handling support.
• Safe Multithreading.
• Supports unlimited number of variables.
• Math expression must be presented as double byte(UNICODE) string.
• Can be extended by user defined functions.
• Target platform : x86 and x64.

You can find list of error messages in EquTypes.h file.

#include <iostream>
#include "EquWin32.h"
#include "EquTypes.h"


// Error handler
void  ErrorHandler(EQUHANDLE hnd, int errCode, const wchar_t* message, const wchar_t* message2)
{
	std::cout << "Error: " << message << ": " << message2 << std::endl;
	throw errCode;
}


//User defined function
TCalc  pow3(TCalc x)
{
	return x * x * x;
}


int main(int argc, char* argv[])
{
	const wchar_t* mathExp = L"1.2e-3+x+2.3*(1-sin(y/3.14)^2)-z";
	const wchar_t* varList = L"x,y,z";
	TCalc args[] = { 1, 2.5, 1.7e-2 };
	TCalc res = TCalc(0);
	EQUHANDLE equHnd = NULL;

	// Initialize EquTranslator algorithm before we can use any function.
	// Return value (handle) must be used in each function call.
	equHnd = ::InitEquTranslator(
		ErrorHandler	//Error callback function
	);

	try
	{
		//Evaluate math expression for a given point "args"
		res = ::Evaluate(equHnd, L"x+y+z", varList, args);
		res = ::Evaluate(equHnd, mathExp, varList, args);

		args[0] = 2.3; args[1] = -5;
		res = ::Evaluate(equHnd, L"x/y+(x^2-y^2)", L"x,y", args);

		//Add user defined function to EquTranslator
		::AddFunction(equHnd, L"p3", pow3);

		// Calculate set of points for one math expression
		// Build it first
		::Build(equHnd, L"3.14*p3(x)+sin(y)-sqrt(z+x)", L"x,y,z");

		res = 0;
		for (int i = 0; i < 10000; i++)
		{
			args[0] = args[0] + 1;
			args[1] = (TCalc)i + 1;
			args[2] = args[0] / args[1];
			// Do calculation for a given point
			res += ::CalcFor(equHnd, args);
		}

		// Another functions to calculate set of points for a given expression.
		::Compile(equHnd, mathExp, varList, args);

		res = 0;
		for (int i = 0; i < 10000; i++)
		{
			args[0] = args[0] + 1;
			args[1] = (TCalc)i + 1;
			args[2] = args[0] / args[1];
			// Do calculation for a given point
			res += ::Run(equHnd);
		}

	}
	catch (int errCode)
	{
		std::cout << "Error code: " << errCode << std::endl;
	}

	// Release resources
	::CloseEquTranslator(equHnd);

	return 0;
}