c - flmoon function in numerical recipies -
i have problem understanding implementation of following function in c: #include <math.h> #define rad (3.14159265/180.0) #include "fulmoon.h" void flmoon(int n, int nph, long *jd, float *frac) { /*this programs begin introductory comment summarizing purpose , explaining calling sequence. routine calculates phases of moon. given integer n , code nph phase desired (nph = 0 new moon, 1 first quarter, 2 full, 3 last quarter), routine returns julian day number jd, , fractional part of day frac added it, of nth such phase since january, 1900. greenwich mean time assumed.*/ int i; float am,as,c,t,t2,xtra; c=n+nph/4.0; t=c/1236.85; t2=t*t; printf("jdhdhdhd"); as=359.2242+29.105356*c; am=306.0253+385.816918*c+0.010730*t2; *jd=2415020+28l*n+7l*nph; xtra=0.75933+1.53058868*c+((1.178e-4)-(1.55e-7)*t)*t2; if (nph == 0 || nph == 2){ xtra += (0.1734-3.93e-4*t)*sin(rad*as)-0.4068*sin(rad*am); } else (nph == 1 || nph == 3){ xtra += (0.1721-4.0e-4*t)*sin(ra...