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Diffstat (limited to 'test/monniaux/glpk-4.65/src/misc/jd.c')
| -rw-r--r-- | test/monniaux/glpk-4.65/src/misc/jd.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/test/monniaux/glpk-4.65/src/misc/jd.c b/test/monniaux/glpk-4.65/src/misc/jd.c new file mode 100644 index 00000000..c9d63171 --- /dev/null +++ b/test/monniaux/glpk-4.65/src/misc/jd.c @@ -0,0 +1,152 @@ +/* jd.c (conversions between calendar date and Julian day number) */ + +/*********************************************************************** +* This code is part of GLPK (GNU Linear Programming Kit). +* +* Copyright (C) 2000-2013 Andrew Makhorin, Department for Applied +* Informatics, Moscow Aviation Institute, Moscow, Russia. All rights +* reserved. E-mail: <mao@gnu.org>. +* +* GLPK is free software: you can redistribute it and/or modify it +* under the terms of the GNU General Public License as published by +* the Free Software Foundation, either version 3 of the License, or +* (at your option) any later version. +* +* GLPK is distributed in the hope that it will be useful, but WITHOUT +* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY +* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public +* License for more details. +* +* You should have received a copy of the GNU General Public License +* along with GLPK. If not, see <http://www.gnu.org/licenses/>. +***********************************************************************/ + +#include <stddef.h> +#include "jd.h" + +/*********************************************************************** +* NAME +* +* jday - convert calendar date to Julian day number +* +* SYNOPSIS +* +* #include "jd.h" +* int jday(int d, int m, int y); +* +* DESCRIPTION +* +* The routine jday converts a calendar date, Gregorian calendar, to +* corresponding Julian day number j. +* +* From the given day d, month m, and year y, the Julian day number j +* is computed without using tables. +* +* The routine is valid for 1 <= y <= 4000. +* +* RETURNS +* +* The routine jday returns the Julian day number, or negative value if +* the specified date is incorrect. +* +* REFERENCES +* +* R. G. Tantzen, Algorithm 199: conversions between calendar date and +* Julian day number, Communications of the ACM, vol. 6, no. 8, p. 444, +* Aug. 1963. */ + +int jday(int d, int m, int y) +{ int c, ya, j, dd; + if (!(1 <= d && d <= 31 && + 1 <= m && m <= 12 && + 1 <= y && y <= 4000)) + return -1; + if (m >= 3) + m -= 3; + else + m += 9, y--; + c = y / 100; + ya = y - 100 * c; + j = (146097 * c) / 4 + (1461 * ya) / 4 + (153 * m + 2) / 5 + d + + 1721119; + jdate(j, &dd, NULL, NULL); + if (d != dd) + return -1; + return j; +} + +/*********************************************************************** +* NAME +* +* jdate - convert Julian day number to calendar date +* +* SYNOPSIS +* +* #include "jd.h" +* int jdate(int j, int *d, int *m, int *y); +* +* DESCRIPTION +* +* The routine jdate converts a Julian day number j to corresponding +* calendar date, Gregorian calendar. +* +* The day d, month m, and year y are computed without using tables and +* stored in corresponding locations. +* +* The routine is valid for 1721426 <= j <= 3182395. +* +* RETURNS +* +* If the conversion is successful, the routine returns zero, otherwise +* non-zero. +* +* REFERENCES +* +* R. G. Tantzen, Algorithm 199: conversions between calendar date and +* Julian day number, Communications of the ACM, vol. 6, no. 8, p. 444, +* Aug. 1963. */ + +int jdate(int j, int *d_, int *m_, int *y_) +{ int d, m, y; + if (!(1721426 <= j && j <= 3182395)) + return 1; + j -= 1721119; + y = (4 * j - 1) / 146097; + j = (4 * j - 1) % 146097; + d = j / 4; + j = (4 * d + 3) / 1461; + d = (4 * d + 3) % 1461; + d = (d + 4) / 4; + m = (5 * d - 3) / 153; + d = (5 * d - 3) % 153; + d = (d + 5) / 5; + y = 100 * y + j; + if (m <= 9) + m += 3; + else m -= 9, + y++; + if (d_ != NULL) *d_ = d; + if (m_ != NULL) *m_ = m; + if (y_ != NULL) *y_ = y; + return 0; +} + +#ifdef GLP_TEST +#include <assert.h> +#include <stdio.h> +#include <stdlib.h> + +int main(void) +{ int jbeg, jend, j, d, m, y; + jbeg = jday(1, 1, 1); + jend = jday(31, 12, 4000); + for (j = jbeg; j <= jend; j++) + { assert(jdate(j, &d, &m, &y) == 0); + assert(jday(d, m, y) == j); + } + printf("Routines jday and jdate work correctly.\n"); + return 0; +} +#endif + +/* eof */ |