Mathc initiation/Fichiers c : c17cd

Sommaire

Installer et compiler ces fichiers dans votre répertoire de travail.

	c00d.c

/* ---------------------------------- */
/* save as c00d.c                     */
/* ---------------------------------- */
#include  "x_hfile.h"
#include       "fd.h"
/* ---------------------------------- */
int main(void)
{
double  ax =     1,   ay =    -1, 
        bx =     4,   by =     2, 
        nx = 2*200,   ny = 2*200,
        
       Mxy =     0,  Myx =     0;

 clrscrn();
 printf(" f : (x,y)-> %s\n\n\n", feq);

 Myx = trapezoid_dydx(f, ay,by,ny, ax,bx,nx);
 Mxy = trapezoid_dxdy(f, ax,bx,nx, ay,by,ny);

 printf(" With the trapezoidal's rule.\n\n");
 printf("    (%.3f  (%.3f\n",     bx,by);
 printf(" int(   int(       %s    Dy Dx = %.6f\n", feq, Myx);
 printf("    (%.3f  (%.3f\n\n\n", ax,ay);
 
 printf("    (%.3f  (%.3f\n",     by,bx);
 printf(" int(   int(       %s    Dx Dy = %.6f\n", feq, Mxy);
 printf("    (%.3f  (%.3f\n\n\n", ay,ax);

 stop();

 return 0;
}
/* ---------------------------------- */
/* ---------------------------------- */

Vous pouvez vérifier avec Octave version 5.2 :

I = dblquad (f, xa, xb, ya, yb)

>> I = dblquad (@(x, y) (2*x+6*x.*x.*y), 1, 4, -1, 2)

I =  234.00

Exemple de sortie écran :

 f : (x,y)-> 2*x+6*x**2*y


 With the trapezoidal's rule.

    (4.000  (2.000
 int(   int(       2*x+6*x**2*y  Dy Dx = 234.000253
    (1.000  (-1.000


    (2.000  (4.000
 int(   int(       2*x+6*x**2*y  Dx Dy = 234.000253
    (-1.000  (1.000


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