F Integration By Weddle's Rule | CodeTheta

### Integration By Weddle's Rule

/******************************************
```     Integration Ry Weddle's Rule
******************************************/
/* http://native-code.blogspot.com */

#include<stdio.h>
#include<conio.h>
#include<math.h>
#define f(x)(exp(-pow(x,2)))

void main()
{
float a,b,h;
float s,s0,s1,s2,s3,s4;

int i,n;

s=s0=s1=s2=s3=s4=0.0F;
clrscr();
//--------------------------

printf("\nEnter the limits:");
scanf("%f %f",&a,&b);

printf("\nEnter the number of subintervals.(Multiples of 6):");
scanf("%d",&n);

h=(b-a)/n;

//--------------------------

s0=(f(a)+f(b));

for(i=1;i<=n-1;i=i+6)
s1+=5*(f(a+i*h)+f(a+(i+4)*h));

for(i=3;i<=n-3;i=i+6)
s2+=6*(f(a+i*h));

for(i=2;i<=n-2;i=i+6)
s3+=(f(a+i*h)+f(a+(i+2)*h));

for(i=6;i<=n-6;i=i+6)
s4+=2*(f(a+i*h));

//--------------------------

s=((3*h)/10)*(s0+s1+s2+s3+s4);

printf("\n\n\nRESULT BY WEDDLE'S RULE:%f",s);
getch();

} // end of main
/* http://native-code.blogspot.com */ ```