Linear Algebra and the C Language/a0g1

/* ------------------------------------ */
/*  Save as :   c00c.c                  */
/* ------------------------------------ */
#include      "v_a.h"
/* ------------------------------------ */
int main(void)
{
double  a[R4*C4]={ 1, 1,1,1,
                   0, 1,9,9,
                   0,-3,9,9,
                   0,-4,9,9 };	

double id[R4*C4]={ 1, 0,0,0,
                   0, 1,0,0,
                   0, 3,1,0,
                   0, 4,0,1 };                
              
double **A  = ca_A_mR(a, i_mR(R4,C4));
double **ID = ca_A_mR(id,i_mR(R4,C4));

double **IDA = mul_mR(ID,A,i_mR(R4,C4));

  clrscrn();
  printf(" Zero under the pivot: \"C2\"\n\n");
  
  printf(" ID:");
  p_mR(ID, S3,P0,C6);
  
  printf(" A:");
  p_mR(A, S3,P0,C6);
  
  printf(" ID A:");
  p_mR(IDA, S5,P1,C6);
  stop();
     
  f_mR(A);
  f_mR(ID);
  f_mR(IDA);
  
  return 0;
}
/* ------------------------------------ */
/* ------------------------------------ */

                                                                                       
 Zero under the pivot: "C2"

 ID:
 +1  +0  +0  +0 
 +0  +1  +0  +0 
 +0  +3  +1  +0 
 +0  +4  +0  +1 

 A:
 +1  +1  +1  +1 
 +0  +1  +9  +9 
 +0  -3  +9  +9 
 +0  -4  +9  +9 

 ID A:
 +1.0  +1.0  +1.0  +1.0 
 +0.0  +1.0  +9.0  +9.0 
 +0.0  +0.0 +36.0 +36.0 
 +0.0  +0.0 +45.0 +45.0 

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