Thread: Trapezoidal Rule for Integration

Hi there, here is my code so far:

Code:

#include <stdio.h>
#include <math.h>


float f(float x)
{
 return(exp(-x*x));
}


float g(float x)
{
 return(exp(-x));
}


float trapeze(float a, float b, float x, float h, float sum, int N, int i)
{
  a = 0.0;
  b = 1.0;


  h = (b - a)/N;
  sum = ((0.5 * h) * (f(a) + f(b)));
  for (i = 1; i < N; i++)   {
    sum = sum + h * f(a + (i * h));
     }
  return (sum);
}




int main (void)
{
  float c, d, e, trap;
  int n;


  printf("Enter the number of intervals: ");
  scanf("%d", &n);
  printf("integral of exp(-x*x): %f\n", trap(c(e)));
  printf("integral of exp(-x): %f\n", trap(d(e)));


  return(0);
}

Ok so, I know there's probably a lot wrong, so I need help as it goes. What I'm supposed to do is find the numerical integration of the functions above using my other function, trapeze. I don't know how to use functions as parameters though.

Also, I'm probably forgetting, but why is my main function not recognizing my trapeze function? Variable names?

So I changed the c, d, e and all that business - now I'm getting that there's too few arguments to function 'trapeze'

Why are there too few arguments?