Aller au contenu

Mathc complexes/07t

Un livre de Wikilivres.


Application

Installer et compiler ces fichiers dans votre répertoire de travail.

c00a.c
/* ------------------------------------ */
/*  Save as :   c00a.c                  */
/* ------------------------------------ */
#include "w_a.h"
/* ------------------------------------ */
/* ------------------------------------ */
#define   RA R3
#define   CA C3
#define   Cb C1 

#define   RXY R3  
#define   CXY C2 
/* ------------------------------------ */
/* ------------------------------------ */
int main(void)
{
double   xy[RXY*CXY] =
                {1,  6,
                 2,  3,
                 3,  5, };

   
double ab[RA*(CA+Cb)]={
/* x**2   x**1     x**0 =  y   */
  +1,   +1,   +1,   +6,
  +4,   +2,   +1,   +3, 
  +9,   +3,   +1,   +5       
};

double **XY =  ca_A_mRZ(xy,i_mZ(RA,C2));

double **Ab =  ca_A_mRZ(ab,i_Abr_Ac_bc_mZ(RA,CA,Cb));
double **A  = c_Ab_A_mZ(Ab,i_mZ(RA,CA));
double **b  = c_Ab_b_mZ(Ab,i_mZ(RA,Cb));

double **A_T        = i_mZ(CA,RA);
double **A_TA       = i_mZ(CA,CA); //         A_T*A
double **invA_TA    = i_mZ(CA,CA); //     inv(A_T*A)
double **invA_TAA_T = i_mZ(CA,RA); //     inv(A_T*A)*A_T

double **x          = i_mZ(CA,Cb); // x = inv(A_T*A)*A_T*b

  clrscrn();
  printf("\n");
  printf(" Find the coefficients a, b, c  of the curve   \n\n");
  printf("      y =  ax**2 + bx + c           (x**0 = 1) \n\n");
  printf(" that passes through the points.               \n\n");
  
  printf("    x     y");
  p_mRZ(XY,S5,P0,C6);
  printf("\n");
  printf(" Using the given points, we obtain this matrix.\n");
  printf("   x**2   x**1     x**0    y\n");
  p_mRZ(Ab,S7,P2,C6);
  stop();

  
  clrscrn();
  printf(" A_T :");
  p_mRZ(transpose_mZ(A,A_T),S10,P2,C7);
  printf(" A_TA :");
  p_mRZ(mul_mZ(A_T,A,A_TA),S10,P2,C7);
  stop();
  
  clrscrn();
  printf(" inv(A_TA) :");
  p_mRZ(inv_mZ(A_TA,invA_TA),S10,P4,C7);  
  printf(" inv(A_TA)*A_T :");
  p_mRZ(mul_mZ(invA_TA,A_T,invA_TAA_T),S10,P4,C7);
  printf("\n x = inv(A_TA)*A_T*b :");
  p_mRZ(mul_mZ(invA_TAA_T,b,x),S10,P4,C7);
  stop();
  
  clrscrn();
  printf("\n x = inv(A_TA)*A_T*b :");
  p_mRZ(x,S10,P2,C7); 
  printf("\n The coefficients a, b, c of the curve are :  \n\n" 
         " y = %+.2fx**2  %+.2fx %+.2f\n\n"
            ,x[R1][C1],x[R2][C1],x[R3][C1]);   
  stop();  

  f_mZ(XY);  
  f_mZ(A);
  f_mZ(b);
  f_mZ(Ab);

  f_mZ(A_T);
  f_mZ(A_TA);       //         A_T*A
  f_mZ(invA_TA);    //     inv(A_T*A)
  f_mZ(invA_TAA_T); //     inv(A_T*A)*A_T
    
  f_mZ(x); 

  return 0;
}
/* ------------------------------------ */
/* ------------------------------------ */
Exemple de sortie écran :
 Find the coefficients a, b, c  of the curve   

      y =  ax**2 + bx + c           (x**0 = 1) 

 that passes through the points.               

    x     y
   +1    +6 
   +2    +3 
   +3    +5 


 Using the given points, we obtain this matrix.
   x**2   x**1     x**0    y

  +1.00   +1.00   +1.00   +6.00 
  +4.00   +2.00   +1.00   +3.00 
  +9.00   +3.00   +1.00   +5.00 

 Press return to continue. 


 A_T :
     +1.00      +4.00      +9.00 
     +1.00      +2.00      +3.00 
     +1.00      +1.00      +1.00 

 A_TA :
    +98.00     +36.00     +14.00 
    +36.00     +14.00      +6.00 
    +14.00      +6.00      +3.00 

 Press return to continue. 


 inv(A_TA) :
   +1.5000    -6.0000    +5.0000 
   -6.0000   +24.5000   -21.0000 
   +5.0000   -21.0000   +19.0000 

 inv(A_TA)*A_T :
   +0.5000    -1.0000    +0.5000 
   -2.5000    +4.0000    -1.5000 
   +3.0000    -3.0000    +1.0000 


 x = inv(A_TA)*A_T*b :
   +2.5000 
  -10.5000 
  +14.0000 

 Press return to continue. 


 x = inv(A_TA)*A_T*b :
     +2.50 
    -10.50 
    +14.00 


 The coefficients a, b, c of the curve are :  

 y = +2.50x**2  -10.50x +14.00

 Press return to continue.