28 lines
674 B
C
28 lines
674 B
C
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#include <math.h>
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#define RAD (3.14159265/180.0)
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void flmoon(int n, int nph, long *jd, float *frac)
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{
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void nrerror(char error_text[]);
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int i;
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float am,as,c,t,t2,xtra;
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c=n+nph/4.0;
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t=c/1236.85;
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t2=t*t;
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as=359.2242+29.105356*c;
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am=306.0253+385.816918*c+0.010730*t2;
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*jd=2415020+28L*n+7L*nph;
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xtra=0.75933+1.53058868*c+((1.178e-4)-(1.55e-7)*t)*t2;
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if (nph == 0 || nph == 2)
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xtra += (0.1734-3.93e-4*t)*sin(RAD*as)-0.4068*sin(RAD*am);
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else if (nph == 1 || nph == 3)
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xtra += (0.1721-4.0e-4*t)*sin(RAD*as)-0.6280*sin(RAD*am);
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else nrerror("nph is unknown in flmoon");
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i=(int)(xtra >= 0.0 ? floor(xtra) : ceil(xtra-1.0));
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*jd += i;
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*frac=xtra-i;
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}
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#undef RAD
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