Thread: math function vs functions...

I have the following problem... i am trying to print out a table of values for the taylor expansion of exp() (as a function) and the plain value of exp().

(i) cant get function to work?

(ii) how might I combine their values on a table?

Many thanks!

include

Code:

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



        double taylor(double x, int n)
    {
        int i;
        double sum = 1.0;
        double term= 1.0;
        for (i=1; i<=n; i++)
        {
        term = (term*x)/i;
        sum=sum+term;
        }          
        
        return sum;
        
        
     }

You'll have to say what you mean by doesn't work. That function looks fine to me.

Your main program should call that function for various values of x and/or n to generate the table.

Your taylor function doesn't look right to me. Maybe you need to refresh your memory.

Here's my quickly cooked up solution:

Code:

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

long factorial( long n )
{
	if( n == 1 )
		return 1;
	else
		return n*factorial(n-1);
}

double exp_maclaurin(double x, int n)
{
	double sum = 1.0;
	int i;
	for(i=1;i<=n;i++)
	{
		sum += pow(x,i)/factorial(i);
	}
	return sum;
}

int main()
{
	printf("Our function: exp(5) = %lf\n", exp_maclaurin(5,10));
	printf("Built-in exp function: exp(5) = %lf\n", exp(5));
	return 0;
}

Hope this helps.

Yes, my apologies. At first glance his taylor function looked incorrect. Disregard my previous post.