Linear Algebra and the C Language/a03c

Install and compile this file in your working directory.

/* ------------------------------------ */
/*  Save as :  c00c.c                   */
/* ------------------------------------ */
#include "v_a.h"
/* ------------------------------------ */
void fun(int rc)
{
double s = r_I(9);

double **A   =    r_mR(    i_mR(rc,rc),9);
double **sA  = smul_mR(s,A,i_mR(rc,rc)  );

   clrscrn();

   printf("A:");
   p_mR(A, S3,P0,C6);
   printf(" %.0f * A:",s);
   p_mR(sA, S3,P0,C6);
   
   printf("\n"
          "      Trace(sA) = %+.0f\n" 
          " %+.0f * Trace( A) = %+.0f\n", trace_R(sA), s, s*trace_R(A));
   
  f_mR(A);
  f_mR(sA);
}
/* ------------------------------------ */
int main(void)
{
time_t t;

  srand(time(&t));
  
   do 
         fun(rp_I(RC5));
        
    while(stop_w());

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

trace(sA) = s*trace(A):

Screen output example:

                                                                                       
A:
 +3  -4  +3 
 +3  -8  +9 
 +5  +7  -2 

 -5 * A:
-15 +20 -15 
-15 +40 -45 
-25 -35 +10 


      Trace(sA) = +35
 -5 * Trace( A) = +35

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