Linear Algebra and the C Language/a0c9


Install and compile this file in your working directory.

/* ------------------------------------ */
/*  Save as :  c00a.c                   */
/* ------------------------------------ */
#include "v_a.h"
/* ------------------------------------ */
#define   RCA        RC5
/* ------------------------------------ */
/* ------------------------------------ */
void fun(void)
{
double **A             = rEsymmetric_mR(i_mR(RCA,RCA),555.,1E-3);
double **cosh_A         =               i_mR(RCA,RCA);

double **EigsVector    =               i_mR(RCA,RCA);
double **T_EigsVector  =               i_mR(RCA,RCA);

double **EigsValue     =               i_mR(RCA,RCA);
double **cosh_EigsValue =               i_mR(RCA,RCA);

double **T1            =               i_mR(RCA,RCA);
  
  clrscrn();
  printf(" A :");
  p_mR(A,S10,P4,C6); 

/* ================================================================== */ 
  eigs_V_mR(A,EigsVector); 
  transpose_mR(EigsVector,T_EigsVector);
      
/* EigsValue : T_EigsVector * A * EigsVector */
  mul_mR(T_EigsVector,A,T1);
  mul_mR(T1,EigsVector,EigsValue);     
  
  printf(" cosh(A):");
  f_eigs_mR(cosh,EigsValue,cosh_EigsValue);  
     mul_mR(EigsVector,cosh_EigsValue,T1);
     mul_mR(T1,T_EigsVector,cosh_A);
     p_mR(cosh_A,S10,P4,C6); 

/* ================================================================== */ 
  eigs_V_mR(cosh_A,EigsVector); 
  transpose_mR(EigsVector,T_EigsVector);  
  
/* EigsValue : T_EigsVector * cosh_A * EigsVector */
  mul_mR(T_EigsVector,cosh_A,T1);
  mul_mR(T1,EigsVector,EigsValue);  

  printf(" acosh(cosh(A)) = A :");
  f_eigs_mR(acosh,EigsValue,cosh_EigsValue); 
     mul_mR(EigsVector,cosh_EigsValue,T1);
     mul_mR(T1,T_EigsVector,A);  
       p_mR(A,S10,P4,C6);

  f_mR(A);
  f_mR(cosh_A);

  f_mR(EigsVector);
  f_mR(T_EigsVector);
  
  f_mR(EigsValue);  
  f_mR(cosh_EigsValue);    
      
  f_mR(T1);
}
/* ------------------------------------ */
int main(void)
{
time_t t;

  srand(time(&t));

do
{
  fun();

} while(stop_w());

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


Screen output example:

                                                                                       
 A :
   +0.0522    -0.0059    +0.0828    +0.0150    -0.0654 
   -0.0059    +0.5696    -0.0106    -0.2065    -0.2950 
   +0.0828    -0.0106    +0.2041    +0.0014    -0.2069 
   +0.0150    -0.2065    +0.0014    +0.3984    -0.1084 
   -0.0654    -0.2950    -0.2069    -0.1084    +0.6454 

 cosh(A):
   +1.0073    +0.0069    +0.0181    +0.0078    -0.0333 
   +0.0069    +1.2420    +0.0296    -0.0880    -0.1813 
   +0.0181    +0.0296    +1.0476    +0.0137    -0.0950 
   +0.0078    -0.0880    +0.0137    +1.1100    -0.0264 
   -0.0333    -0.1813    -0.0950    -0.0264    +1.3012 

 acosh(cosh(A)) = A :
   +0.0522    -0.0059    +0.0828    +0.0150    -0.0654 
   -0.0059    +0.5696    -0.0106    -0.2065    -0.2950 
   +0.0828    -0.0106    +0.2041    +0.0014    -0.2069 
   +0.0150    -0.2065    +0.0014    +0.3984    -0.1084 
   -0.0654    -0.2950    -0.2069    -0.1084    +0.6454 


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