C program for eulers method for solving a differential equation with intial conditions

to solve

dy/dx = f(x,y)

y(x0) = y0

f(x,y) is being evaluated as a separate function “funct” which can be suitably adjusted

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




float funct(float x,float y)
{

   float f;
   /*edit f into required function*/

   f= (x+y)/2 ;



   return (f);
}

void clearline(int i)
 {
 /*funtion for clearing "i" lines */
int j;
for(j=1; j<=i;j=j+1)

	printf("\n");

 }

main()
{
  float x,y,x0,y0,xn,yn,xcurr=0,ycurr,xnext,ynext,h;
  int n=0;


   clearline(50);

 printf("\nEnter the initial values:x0=");
  scanf("%f",&x0);
   printf("Enter the initial values:y0=");
  scanf("%f",&y0);

   printf("Enter the final value of x for which y is required:xn=");
  scanf("%f",&xn);
  printf("Enter the value ofh, h=");
  scanf("%f",&h);

  xcurr=x0;
  ycurr=y0;

  iterat:

	    if(h>0 && xcurr>=xn)
			 goto end;


	    if(h<0 && xcurr<=xn)
			 goto end;

	    ynext = ycurr + h*funct(xcurr,ycurr);
	    xnext = xcurr + h;

	     printf("y[%f] = %f \n ",xnext,ynext);
	     xcurr = xnext;
	     ycurr = ynext;

	       n=n+1;

	      if((n%10)==0)
	      {printf("press enter to continue");
		getch();
		printf("\n");

		}
	    goto iterat;

end:
getch();

      }

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