Mathc matrices/c09a08

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	inv08.c

/* ------------------------------------ */
/*  Save as :   inv08.c                 */
/* ------------------------------------ */
#include "v_a.h"
/* ------------------------------------ */
/* ------------------------------------ */
double **xx_sort_c_mR(
double **Ab
)
{
double **T = i_RC_mR(Ab[R_SIZE][C0],Ab[C_SIZE][C0]);
int c;

  for(c=C1; c<Ab[C_SIZE][C0]; c++)

           c_c_withR0_mR(  Ab,        c,
                            T, Ab[R0][c]);
 c_withR0_mR(T,Ab);
  
 f_mR(T);
 
 return(Ab);
}
/* ------------------------------------ */
/* ------------------------------------ */
double **XX_invgj_mR(
double **A,
double **invA
)
{
double **ID = i_RC_mR(A[R_SIZE][C0],A[C_SIZE][C0]);
double **AID;

int r = A[R_SIZE][C0];

  r--;

  AID = i_Abr_Ac_bc_mR(r,r,r);

       eye_mR(ID);
  c_A_b_Ab_mR(A,ID,AID);
   invgj_pivot_mR(AID);
    xx_sort_c_mR(AID);
    sort_r_mR(AID);
   c_Inv_A_mR(AID,invA);

  f_mR(AID);
  f_mR(ID);

return(invA);
}
/* ------------------------------------ */
/* ------------------------------------ */
void fun(int r)
{
double **A   = r_mR( i_mR(r,r), 99.);
double **Inv =       i_mR(r,r);
double **AInv =      i_mR(r,r);

  clrscrn();

  XX_invgj_mR(A,Inv);
  
  printf(" Copy/Past into the octave window.\n\n");
  printf("format short e\n");
  p_Octave_mR(A,"A",P0);
   
  printf(" inv(A)");
  pE_mR(Inv,S12,P4,C6);

  printf(" A * inv(A)");
  mul_mR(A,Inv,AInv);
  p_mR(AInv,S12,P4,C6);
  
  f_mR(AInv);  
  f_mR(Inv);
  f_mR(A);
}
/* ------------------------------------ */
int main(void)
{
time_t t;

  srand(time(&t));
  
do
{
   fun(rp_I(C2)+C2);

} while(stop_w());

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

Nous allons voir une nouvelle fonction, sort_c_mR(); que nous appellerons xx_sort_c_mR();


Exemple de sortie écran :

 ------------------------------------ 
 Copy/Past into the octave window.

format short e
 A=[
-73,+14,-97;
+38,+78,-87;
-43,+94,-39]

 inv(A)
 -5.2751e-03  +8.8042e-03  -6.5199e-03 
 -5.3645e-03  +1.3599e-03  +1.0309e-02 
 -7.1136e-03  -6.4296e-03  +6.3946e-03 

 A * inv(A)
     +1.0000      +0.0000      +0.0000 
     +0.0000      +1.0000      +0.0000 
     -0.0000      +0.0000      +1.0000 


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