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function radtrans_jd(i,j,k) |
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c |
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c |
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c This function converts a calendar date to the corresponding Julian |
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c day starting at noon on the calendar date. The algorithm used is |
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c from Van Flandern and Pulkkinen, Ap. J. Supplement Series 41, |
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c November 1979, p. 400. |
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c |
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c |
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c Arguments |
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c |
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c Name Type I/O Description |
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c ---- ---- --- ----------- |
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c i I*4 I Year - e.g. 1970 |
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c j I*4 I Month - (1-12) |
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c k I*4 I Day - (1-31) |
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c jd I*4 O Julian day |
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c |
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c external references |
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c ------------------- |
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c none |
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c |
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c |
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c Written by Frederick S. Patt, GSC, November 4, 1992 |
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c |
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c |
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INTEGER radtrans_jd,i,j,k |
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|
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radtrans_jd = 367*i - 7*(i+(j+9)/12)/4 + 275*j/9 + k + 1721014 |
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|
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c This additional calculation is needed only for dates outside of the |
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c period March 1, 1900 to February 28, 2100 |
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c radtrans_jd = radtrans_jd + 15 - 3*((i+(j-9)/7)/100+1)/4 |
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|
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return |
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end |