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Mathc complexes/07w

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Application

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c00d.c
/* ------------------------------------ */
/*  Save as :   c00d.c                  */
/* ------------------------------------ */
#include "w_a.h"
/* ------------------------------------ */
/* ------------------------------------ */
#define   RA R4
#define   CA C4
#define   Cb C1 

#define   RXY R4  
#define   CXY C2 
/* ------------------------------------ */
/* ------------------------------------ */
int main(void)
{
double   xy[RXY*CXY] ={
                   -5,    -8,
                   -2,     8,
                    2,    -8,
                    5,     8};

double ab[RA*(CA+Cb)]={
/* x**3    x**2    x**1    x**0     y   */
-125,  +25,   -5,   +1,   -8, 
  -8,   +4,   -2,   +1,   +8, 
  +8,   +4,   +2,   +1,   -8, 
+125,  +25,   +5,   +1,   +8,     
};

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**3 + bx**2 + cx + d            \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**3    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**3 %+.2fx \n\n"
            ,x[R1][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**3 + bx**2 + cx + d            

 that passes through the points.             

    x     y
   -5    -8 
   -2    +8 
   +2    -8 
   +5    +8 


 Using the given points, we obtain this matrix.
   x**3    x**2    x**1    x**0     y

-125.00  +25.00   -5.00   +1.00   -8.00 
  -8.00   +4.00   -2.00   +1.00   +8.00 
  +8.00   +4.00   +2.00   +1.00   -8.00 
+125.00  +25.00   +5.00   +1.00   +8.00 

 Press return to continue. 


 A_T :
   -125.00      -8.00      +8.00    +125.00 
    +25.00      +4.00      +4.00     +25.00 
     -5.00      -2.00      +2.00      +5.00 
     +1.00      +1.00      +1.00      +1.00 

 A_TA :
 +31378.00      +0.00   +1282.00      +0.00 
     +0.00   +1282.00      +0.00     +58.00 
  +1282.00      +0.00     +58.00      +0.00 
     +0.00     +58.00      +0.00      +4.00 

 Press return to continue. 


 inv(A_TA) :
   +0.0003    -0.0000    -0.0073    +0.0000 
   -0.0000    +0.0023    +0.0000    -0.0329 
   -0.0073    +0.0000    +0.1779    -0.0000 
   +0.0000    -0.0329    -0.0000    +0.7268 

 inv(A_TA)*A_T :
   -0.0048    +0.0119    -0.0119    +0.0048 
   +0.0238    -0.0238    -0.0238    +0.0238 
   +0.0190    -0.2976    +0.2976    -0.0190 
   -0.0952    +0.5952    +0.5952    -0.0952 


 x = inv(A_TA)*A_T*b :
   +0.2667 
   +0.0000 
   -5.0667 
   +0.0000 

 Press return to continue. 


 x = inv(A_TA)*A_T*b :
     +0.27 
     +0.00 
     -5.07 
     +0.00 


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

 y = +0.27x**3 -5.07x 

 Press return to continue.