Linear Algebra and the C Language/a0fe

/* ------------------------------------ */
/*  Save as :   c00a.c                  */
/* ------------------------------------ */
#include "v_a.h"
/* ------------------------------------ */
/* ------------------------------------ */
void X_c_Inv_A_mR(
double **AID,
double **invA
)
{
int r;
int c;
int RC = AID[C_SIZE_A][C0];
   
    --RC;
    
 	for    (r=R1; r<invA[R_SIZE][C0]; r++)
 	   for (c=C1; c<invA[C_SIZE][C0]; c++)

            invA[r][c] = AID[r][c+RC];
}
/* ------------------------------------ */
/* ------------------------------------ */
void fun(int r)
{
double **A  = i_mR(r,r);
double **b  = i_mR(r,r);
double **Ab = i_Abr_Ac_bc_mR(   r,  r,  r);
/*            i_Abr_Ac_bc_mR(R_Ab,C_A,C_b));  */
double **invA = i_mR(r,r);

 do
  {
   r_mR(A,999.);
   printf(".");
  }while(!det_R(A));

  clrscrn();
  printf(" A :");
  p_mR(A, S8,P0,C4);

  printf("   b : ID :");
  eye_mR(b);
  p_mR(b, S8,P0,C4);
  stop();
  
  clrscrn();  
  printf(" Ab :");
  c_A_b_Ab_mR(A,b,Ab);
  p_mR(Ab, S8,P0,C4);
  printf("  gj_TP_mR(Ab) :");  
  gj_TP_mR(Ab);
  p_mR(Ab, S8,P4,C4);
  stop();
  
  clrscrn(); 
  printf(" Copy/Past into the octave window.\n\n");
  p_Octave_mR(A,"A",P0);
  printf("format short e\n");
  printf(" inv(A)\n\n");

  printf(" invA : c_Inv_A_mR(Ab,invA);");  
  c_Inv_A_mR(Ab,invA);
  pE_mR(invA, S14,P4,C4);
  
  f_mR(invA);
  f_mR(Ab);
  f_mR(b);
  f_mR(A);
}
/* ------------------------------------ */
int main(void)
{
time_t t;

  srand(time(&t));
do
{
  fun(R4);
} while(stop_w());

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

                                                                                       
 A :
    +498     -467     -231     +109 
    -835     +153     +787     -191 
    -217     -939     -379     +418 
    +888     -337     +608     -150 

   b : ID :
      +1       +0       +0       +0 
      +0       +1       +0       +0 
      +0       +0       +1       +0 
      +0       +0       +0       +1 

 Press return to continue. 


 Ab :
    +498     -467     -231     +109 
    -835     +153     +787     -191 
    -217     -939     -379     +418 
    +888     -337     +608     -150 

      +1       +0       +0       +0 
      +0       +1       +0       +0 
      +0       +0       +1       +0 
      +0       +0       +0       +1 

  gj_TP_mR(Ab) :
 +1.0000  +0.0000  +0.0000  +0.0000 
 +0.0000  +1.0000  +0.0000  +0.0000 
 +0.0000  +0.0000  +1.0000  +0.0000 
 -0.0000  -0.0000  -0.0000  +1.0000 

 -0.0017  -0.0012  +0.0003  +0.0011 
 -0.0057  -0.0022  +0.0009  +0.0013 
 -0.0052  -0.0012  +0.0016  +0.0022 
 -0.0185  -0.0067  +0.0061  +0.0055 

 Press return to continue. 


 Copy/Past into the octave window.

 A=[
+498,-467,-231,+109;
-835,+153,+787,-191;
-217,-939,-379,+418;
+888,-337,+608,-150]

format short e
 inv(A)

 invA : c_Inv_A_mR(Ab,invA);
   -1.7278e-03    -1.1824e-03    +2.8845e-04    +1.0538e-03 
   -5.7200e-03    -2.2488e-03    +9.3871e-04    +1.3227e-03 
   -5.2021e-03    -1.1816e-03    +1.6056e-03    +2.1986e-03 
   -1.8463e-02    -6.7368e-03    +6.1066e-03    +5.5119e-03 


 Press   return to continue
 Press X return to stop