1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
|
#include <stdio.h>
#include <gsl/gsl_math.h>
#include <gsl/gsl_sf_legendre.h>
#include <gsl/gsl_sf_alf.h>
int
main(void)
{
const size_t lmax = 5;
const size_t plm_size = gsl_sf_legendre_array_n(lmax);
const size_t nlm = gsl_sf_legendre_nlm(lmax);
const size_t idx21 = gsl_sf_legendre_array_index(2, 1);
double * Plm = malloc(plm_size * sizeof(double));
double * dPlm = malloc(nlm * sizeof(double));
double * d2Plm = malloc(nlm * sizeof(double));
double x;
for (x = -0.99; x <= 0.99; x += 0.01)
{
gsl_sf_legendre_deriv2_alt_array(GSL_SF_LEGENDRE_SPHARM, lmax, x, Plm, dPlm, d2Plm);
printf("%f %e %e %e\n", x, Plm[idx21], dPlm[idx21], d2Plm[idx21]);
}
free(Plm);
free(dPlm);
free(d2Plm);
return 0;
}
|
