Linear Algebra and the C Language/a0md

Install and compile this file in your working directory.

/* ------------------------------------ */ /* Save as : c00b.c */ /* ------------------------------------ */ #include "v_a.h" /* ------------------------------------ */  #define RCA RC3  #define EVALUE RC3  /* ------------------------------------ */  /* ------------------------------------ */ void fun(void) {  double a[RCA*RCA] ={  +1.345288030, +1.760536858, -1.232763852,  +1.760536858, +4.139646496, +0.479295438,  -1.232763852, +0.479295438, +3.515065475  };   double **A = ca_A_mR(a, i_mR(RCA,RCA)); double **V = eigs_V_mR(A, i_mR(RCA,RCA)); double **V3 = c_c_mR(V,EVALUE, i_mR(RCA, C1),C1); double **AV3 = mul_mR(A,V3, i_mR(RCA, C1));   clrscrn();   printf(" We know: A V3 = EVALUE3 V3 \n\n"  " Verify if A V3 = 0 with A!= 0 and V3 != 0\n\n"  " When EVALUE3 = 0 \n\n");  stop();    clrscrn();   printf(" A:");  p_mR(A, S9,P5, C3);   printf(" V:");  p_mR(V, S9,P5, C4);     printf(" V%d:",EVALUE);  p_mR(V3, S9,P5, C3);  printf(" A V%d:",EVALUE);  p_mR(AV3, S9,P5, C3);  stop();    f_mR(A);  f_mR(V);   f_mR(V3);   f_mR(AV3);  } /* ------------------------------------ */ int main(void) {  fun();    return 0; } /* ------------------------------------ */ /* ------------------------------------ */ 

Screen output example:

   We know: A V3 = EVALUE3 V3   Verify if A V3 = 0 with A!= 0 and V3 != 0  When EVALUE3 = 0   Press return to continue.   A:  +1.34529 +1.76054 -1.23276   +1.76054 +4.13965 +0.47930   -1.23276 +0.47930 +3.51507   V:  +0.45779 -0.27269 +0.84621   +0.88400 +0.24101 -0.40057   -0.09471 +0.93143 +0.35139   V3:  +0.84621   -0.40057   +0.35139   A V3:  +0.00000   -0.00000   +0.00000   Press return to continue.