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Mathc matrices/c25e

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Application


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c02b.c
/* ------------------------------------ */
/*  Save as :   c02b.c                  */
/* ------------------------------------ */
#include "v_a.h" 
/* ------------------------------------ */
/* ------------------------------------ */
#define   RCB RC3
/* ------------------------------------ */
/* ------------------------------------ */
void fun(void)
{
	
double tx[RCB*C1]={
 -7, 
 -6, 
 +8 
};

double tB[RCB*RCB]={
+0.4819, +0.4615, +0.7448, 
+0.6196, -0.7806, +0.0828, 
+0.6196, +0.4216, -0.6621 
};
	
double **B      =    ca_A_mR(tB,i_mR(RCB,RCB));  
double **invB   =    inv_mR(B,  i_mR(RCB,RCB));

double **b[RCB];

double **x      = ca_A_mR(tx,i_mR(RCB,C1));
double **x_b    =            i_mR(RCB,C1)    ;
int c;

/* ------------------------------------ */
/* ------------------------------------ */
  for(c=C0; c<csize_R(B); c++)
     {
      b[c] = i_mR(RCB,C1);      
      c_c_mR(B,(c+C1),b[c],C1); }

      
/* ------------------------------------ */
/* ------------------------------------ */      
  clrscrn();
  printf(" B is the change of basis matrix for the basis \"B\" \n\n"
         " B :             orthonormal matrix");
  p_mR(B,S10,P4,C7);
  printf("invB :              invB == B_T");
  p_mR(invB,S10,P4,C7);
  stop();  
  
/* ------------------------------------ */
/* ------------------------------------ */     
  clrscrn();
  printf(" x :");      
  p_mR(x,S10,P4,C6); 
  printf("  Compute x in the B basis :\n\n"
         " x_b         = invB * x :");
  p_mR(mul_mR(invB,x,x_b),S10,P4,C7);  
  stop();  
  
/* ------------------------------------ */
/* ------------------------------------ */  
  clrscrn();
  printf(" x :");      
  p_mR(x,S10,P4,C6); 
  
  printf("   b[0]       b[1]    ...           b[n]\n");
  p_mR(B,S10,P4,C7);
  
  printf(" Compute x in the B basis : \n\n"
         " x_b :                 x_b = <b[i],x>\n");
         
  for(c=C0; c<csize_R(B); c++)   
      printf("%+10.4f   <b[%d],x>\n",dot_R(b[c],x),c);
      
  printf("\n\n"); 
     
  stop();  
/* ------------------------------------ */
/* ------------------------------------ */   
  clrscrn(); 

  printf(" Compute x in the B basis : \n\n"
         " x_b  :                x_b = invB * x");      
  p_mR(x_b,S10,P4,C6); 
  
  printf(" x_b :                 x_b = <b[i],x>\n");
         
  for(c=C0; c<csize_R(B); c++)   
      printf("%+10.4f   <b[%d],x>\n",dot_R(b[c],x),c); 

   printf("\n\n");         
/* ------------------------------------ */
/* ------------------------------------ */

  for(c=C0; c<csize_R(B); c++)
  
       f_mR(b[c]); 

  f_mR(x);        
  f_mR(B);
  f_mR(invB);
}
/* ------------------------------------ */
int main(void)
{

  fun();

  return 0;
}

/* ------------------------------------ */
/* ------------------------------------ */


Présentation deux deux algorithmes pour calculer la valeur de x en base b

                 x_b = invB * x

                 x_b = <b[i],x>


Exemple de sortie écran :
 --------------------------------
 B is the change of basis matrix for the basis "B" 

 B :             orthonormal matrix
   +0.4819    +0.4615    +0.7448 
   +0.6196    -0.7806    +0.0828 
   +0.6196    +0.4216    -0.6621 

invB :              invB == B_T
   +0.4819    +0.6195    +0.6196 
   +0.4615    -0.7805    +0.4216 
   +0.7449    +0.0828    -0.6621 

 Press return to continue. 


 --------------------------------
 x :
   -7.0000 
   -6.0000 
   +8.0000 

  Compute x in the B basis :

 x_b         = invB * x :
   -2.1340 
   +4.8250 
  -11.0074 

 Press return to continue. 


 --------------------------------
 x :
   -7.0000 
   -6.0000 
   +8.0000 

   b[0]       b[1]    ...           b[n]

   +0.4819    +0.4615    +0.7448 
   +0.6196    -0.7806    +0.0828 
   +0.6196    +0.4216    -0.6621 

 Compute x in the B basis : 

 x_b :                 x_b = <b[i],x>
   -2.1341   <b[0],x>
   +4.8259   <b[1],x>
  -11.0072   <b[2],x>


 Press return to continue. 


 --------------------------------
 Compute x in the B basis : 

 x_b  :                x_b = invB * x
   -2.1340 
   +4.8250 
  -11.0074 

 x_b :                 x_b = <b[i],x>
   -2.1341   <b[0],x>
   +4.8259   <b[1],x>
  -11.0072   <b[2],x>