oldtests/gsl_leg_phase.c

   1 #include <stddef.h>
   2 #include <gsl/gsl_sf_legendre.h>
   3 #include <stdio.h>
   4
   5 int main() {
   6   const size_t lmax = 2;
   7   const double x = .5;
   8   size_t arrsiz = gsl_sf_legendre_array_n(lmax);
   9   double csphase = 1;
  10   double target[arrsiz];
  11   printf("lmax = %zd, x = %g, csphase = %g:\n", lmax, x, csphase);
  12   gsl_sf_legendre_array_e(GSL_SF_LEGENDRE_NONE, lmax, x, csphase, target);
  13   for(int l = 0; l <= lmax; ++l) for (int m = 0; m <= l; ++m)
  14     printf("P_%d^%d(%g)\t= %g\n", l, m, x, target[gsl_sf_legendre_array_index(l,m)]);
  15   csphase = -1;
  16   printf("lmax = %zd, x = %g, csphase = %g:\n", lmax, x, csphase);
  17   gsl_sf_legendre_array_e(GSL_SF_LEGENDRE_NONE, lmax, x, csphase, target);
  18   for(int l = 0; l <= lmax; ++l) for (int m = 0; m <= l; ++m)
  19     printf("P_%d^%d(%g)\t= %g\n", l, m, x, target[gsl_sf_legendre_array_index(l,m)]);
  20   return 0;
  21 }
  22