Linear Algebra and the C Language/a0g7

Install and compile this file in your working directory.

/* ------------------------------------ */
/*  Save as :   c00c.c                  */
/* ------------------------------------ */
#include      "v_a.h"
/* ------------------------------------ */
int main(void)
{
double  a[R3*C3]={    2,9,9,
                      1,9,9,
                      1,9,9 };
                      	
double id[R3*C3]={1./2.,0,0,
                      0,1,0,
                      0,0,1 };                
              
double **A  = ca_A_mR(a,    i_mR(R3,C3));
double **ID = ca_A_mR(id,   i_mR(R3,C3));

double **AID = mul_mR(A,ID, i_mR(R3,C3));

  clrscrn();
  printf("  Put the pivot at one: [R1,C1]\n\n");
  
  printf(" ID:");
  p_mR(ID, S3,P2,C6);
  
  printf(" A:");
  p_mR(A, S3,P2,C6);
  
  printf(" A ID:");
  p_mR(AID, S3,P2,C6);
  stop();
     
  f_mR(A);
  f_mR(ID);
  f_mR(AID);

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

 Put the pivot at one:

Screen output example:

                                                                                       
 Put the pivot at one: [R1,C1]

 ID:
+0.50 +0.00 +0.00 
+0.00 +1.00 +0.00 
+0.00 +0.00 +1.00 

 A:
+2.00 +9.00 +9.00 
+1.00 +9.00 +9.00 
+1.00 +9.00 +9.00 

 A ID:
+1.00 +9.00 +9.00 
+0.50 +9.00 +9.00 
+0.50 +9.00 +9.00 

 Press return to continue.