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ocssw_src
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viirs_sim_sdr
time_utl.c
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1
/*
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subroutine jddate(jd,i,j,k)
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C
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C This routine computes the calendar date corresponding to
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C a given Julian day. This code was brazenly copied from
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C a routine written by Myron Shear for CSC on Julian Day 1.
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C
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C ARGUMENT TYPE I/O DESCRIPTION
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C __________________________________________________________
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C JD I*4 I Julian Day (reference Jan 1, 4713 BC)
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C I I*4 O Year
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C J I*4 O Month
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C K I*4 0 Day of Month
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C
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l = jd + 68569
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n = 4*l/146097
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l = l - (146097*n + 3)/4
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i = 4000*(l+1)/1461001
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l = l - 1461*i/4 + 31
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j = 80*l/2447
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k = l - 2447*j/80
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l = j/11
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j = j + 2 - 12*l
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i = 100*(n-49) + i + l
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return
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end
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*/
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/*
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subroutine jdate(jd,i,k)
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C
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C This routine computes the year and day-of-year corresponding
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C to a given Julian day. This algorithm is designed for the
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C period 1900 - 2100.
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C
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C ARGUMENT TYPE I/O DESCRIPTION
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C __________________________________________________________
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C JD I*4 I Julian Day (reference Jan 1, 4713 BC)
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C I I*4 O Year
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C K I*4 0 Day of Year
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C
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c Program written by: Frederick S. Patt
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c General Sciences Corporation
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c May 12, 1993
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c Compute days since January 0, 1900
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l = jd - 2415020
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c Compute years since 1900
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i = 4*l/1461
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c Compute day-of-year
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k = l - 1461*(i-1)/4 - 365
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c Add first two digits of year
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i = i + 1900
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return
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end
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*/
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/*
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function 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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jd = 367*i - 7*(i+(j+9)/12)/4 + 275*j/9 + k + 1721014
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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 jd = jd + 15 - 3*((i+(j-9)/7)/100+1)/4
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return
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end
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*/
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int
jd_c
(
int
y
,
int
m,
int
d) {
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return
( 367 *
y
-
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7 * (
y
+ (m + 9) / 12) / 4 +
100
275 * m / 9 +
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d + 1721014);
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}
jd_c
int jd_c(int y, int m, int d)
Definition:
time_utl.c:97
color_dtdb.y
y
Definition:
color_dtdb.py:430
