/*
  Name: tp4-ex3a
  Copyright: b1-1
  Author: ARCHAMBEAU
  Date: 13/09/06 14:07
  Description: racine carrée
*/

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

int main(void)
 {
     float racine,
           a,
           Xj,
           Yj=1,   /* correspond à Xcoef(j-1)*/
                   /*  et Xcoef0 = 1         */
           e=1,
           val_exact;
     int   j = 0;
     
     printf ("Calcul de la racine carree d'un nombre reel\n");
     printf ("Saisie d'un nombre A : ");
     scanf ("%f", &a);
     
     printf("----------------------------------------\n");
     printf(" Indice j |  racine A    |    SQRT (A)\n");
     printf("----------------------------------------\n");
     
     while (e>0.0001)
     {
       Xj = (Yj + a/Yj)/2;
       e = fabs( Xj-Yj);   /*  fabs(x)  c'est la valeur absolu de x   */
       Yj = Xj;
       j=j+1;
       val_exact=sqrt (a);
       printf("   %6d | %12.6f | %12.6f \n", j, Xj, val_exact);
     }
     printf("----------------------------------------\n");
     
     system ("pause");
     return 0;
 }