muParser - a fast math parser library
Version 2.1.0
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muParser
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### Introduction

About the parser
Release notes
News
Software using muParser
Licence

### Features

Features
Overview
Built in functions
Built in binary operators
Other operators

### Build instructions

Building on Win32
Building on BSD/Linux
Misc build instructions
Including the files
Compiler switches
Where to ask for help

### Math parser interface

Parser (de)initialization
Evaluating an expression
Single return value
Multiple return values
Bulk mode
Setting the expression
Defining identifier charsets
Defining parser variables
Explicit variable definition
Implicit variable definition
Defining constants
Adding functionand operators
Defining functions
Defining operators
Unary operators
Binary operators
Querying variables
Querying constants
Value recognition callbacks
Removing variables/constants
Localization
Error handling
Example code

### Current version

Benchmarks

## Example code

If you put all this together, you get the source code for a small application. The application defines a parser variables ("`a`") and adds a user defined functions named "`MyFunc`". When using the parser make sure that you don't forget to catch the `Parser::exception_type` in your application. It contains detailed information helping you to find syntax errors in your formula.

    #include <iostream>
    #include "muParser.h"

    // Function callback
    double MySqr(double a_fVal)
    {
      return a_fVal*a_fVal;
    }

    // main program
    int main(int argc, char* argv[])
    {
      using namespace mu;

      try
      {
        double fVal = 1;
        Parser p;
        p.DefineVar("a", &fVal);
        p.DefineFun("MySqr", MySqr);
        p.SetExpr("MySqr(a)*_pi+min(10,a)");

        for (std::size_t a=0; a<100; ++a)
        {
          fVal = a;  // Change value of variable a
          std::cout << p.Eval() << std::endl;
        }
      }
      catch (Parser::exception_type &e)
      {
        std::cout << e.GetMsg() << std::endl;
      }
      return 0;
    }

## Benchmarks

Finally, I'd like to give you some benchmarks. The benchmarking was done on an Intel Pentium P-4 with 2.6 GHz, with a version compiled by using MSVC++ 7.1 (Standard edition). The diagram shows number of evaluations per seconds vs. expression length. I compared both the static lib and the dll version with two other parsers that are freely available on the net, very fast and have a similar set of features. One of them is a commercial product.

A higher curve means better performance. Expressions were created randomly. They used only `sin` and `cos` functions and contained multiple variables and constants. In order to smoothen the curves each point represents the value of a running average over 10 sample expressions.

© 2005-2011 Ingo Berg | ^ TOP