2017-04-10 07:03:10 +03:00
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#include <math.h>
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#include "gaunt.h"
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2017-04-10 13:48:06 +03:00
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static const double sqrtpi = 1.7724538509055160272981674833411451827975494561223871;
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//static const double ln2 = 0.693147180559945309417232121458176568075500134360255254120;
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// Associated Legendre polynomial at zero argument (DLMF 14.5.1)
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double legendre0(int m, int n) {
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return pow(2,m) * sqrtpi / gamma(.5*n - .5*m + .5) / gamma(.5*n-.5*m);
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}
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// Derivative of associated Legendre polynomial at zero argument (DLMF 14.5.2)
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double legendreD0(int m, int n) {
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return -2 * legendre0(m, n);
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}
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