What is the best way to evaluate mathematical expressions in C++?

by

Not sure why ‘pow’ only has one parameter, but using the ExprTk library one can derive the following simple solution:

#include <cstdio>
#include <string>
#include "exprtk.hpp"

int main()
{
   typedef exprtk::expression<double> expression_t;
   typedef exprtk::parser<double>         parser_t;

   std::string expression_string = "3 + sqrt(5) + pow(3,2) + log(5)";

   expression_t expression;

   parser_t parser;

   if (parser.compile(expression_string,expression))
   {
     double result = expression.value();

     printf("Result: %19.15\n",result);
   }
   else
     printf("Error in expression\n.");

   return 0;
}

More Related Contents:

  1. how can i increase the speed of my C++ calculation [closed]
  2. How to find out the date of the first day of week from the week number in C++
  3. Not able to calculate in C.How do you calculate in C?
  4. C++ quadratic equation using factorization
  5. Why does my code work? Simple arithmetics
  6. Integer division always zero [duplicate]
  7. How approximation search works
  8. Can’t make value propagate through carry
  9. How does photoshop blend two images together? [closed]
  10. Fast ceiling of an integer division in C / C++
  11. Direct way of computing clockwise angle between 2 vectors
  12. How to achieve smooth tangent space normals?
  13. Calculating (a^b)%MOD
  14. What is this smiley-with-beard expression: “”?
  15. Most accurate way to do a combined multiply-and-divide operation in 64-bit?
  16. Uses of a C++ Arithmetic Promotion Header
  17. Most efficient/elegant way to clip a number?
  18. How do I implement a Bézier curve in C++?
  19. sine wave that slowly ramps up frequency from f1 to f2 for a given time
  20. Impact of cubic and catmull splines on image
  21. What are the most widely used C++ vector/matrix math/linear algebra libraries, and their cost and benefit tradeoffs? [closed]
  22. Convert string to mathematical evaluation [closed]
  23. What is the C++ function to raise a number to a power?
  24. Inverting a 4×4 matrix
  25. Optimizations for pow() with const non-integer exponent?
  26. OpenSouce C/C++ Math expression parser Library [closed]
  27. self made pow() c++
  28. Area of rectangle-rectangle intersection
  29. Finding square root without using sqrt function?
  30. Is there any advantage to using pow(x,2) instead of x*x, with x double?

Leave a Comment