Linear Algebra and the C Language/a0jk

Install and compile this file in your working directory.

/* ------------------------------------ */
/*  Save as :   c00a.c                  */
/* ------------------------------------ */
#include "v_a.h"
/* ------------------------------------ */
void fun(void)
{ 
double s = r_I(9);

double **U_T   =    r_mR(         i_mR(R1,C3), 9);  
double **V_T   = smul_mR(s,U_T,   i_mR(R1,C3));    
 
double **UxV_T =  UxV_mR(U_T,V_T, i_mR(R1,C3));
   
  clrscrn();
  printf("  s = %+.0f\n\n",s);         
  printf("  u_T:");
  p_mR(U_T, S4, P0, C6);
  printf("  v_T:");
  p_mR(V_T, S4, P0, C6);

  printf("\n\n"
         " If u and v are colinear then u x v == 0\n\n"
         "    (uxv):" );    
  p_mR(UxV_T, S5, P0, C6);
  
  f_mR(U_T); 
  f_mR(V_T); 
}
/* ------------------------------------ */
int main(void)
{
time_t t;

  srand(time(&t));
  
do
{  
  fun();

} while(stop_w());

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

If u and v are colinear then u x v == 0:

Screen output example:

  s = -3

  u_T :
  +8   +7   +7 

  v_T :
 -24  -21  -21 



 If u and v are colinear then u x v == 0

    (uxv) :
   +0    -0    +0 


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