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moon.c
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/*
* moon.c
* arrenged by H.Tsujimura 1989,1990,1991,1995,1998,1999,2000,
* 2001,2002
* Last updated: 20th December 2002
*
* This program is for computing the phase of the moon.
*
* History :
* $Log: moon.c $
* Revision 1.2 2003/11/11 07:02:19 tsujimura543
* K&R 表記 → ANSI C 表記 に完全移行
*
* Revision 1.1 2003/10/24 01:35:04 tsujimura543
* Initial revision (renewal)
*
* Revision 1.69 2003/03/03 12:09:08 tsujimura543
* バグ修正 (参照している変数が間違っていた)
*
* Revision 1.68 2003/03/03 12:07:41 tsujimura543
* CGI にパラメータを渡せるようにした
*
* Revision 1.67 2003/02/24 09:25:42 tsujimura543
* 実行形式の拡張子が .cgi の場合、Content-type: 行を出力するようにした
*
* Revision 1.66 2003/02/07 08:08:35 tsujimura543
* 起動時オプションとして -H, -v を正式サポート
*
* Revision 1.65 2002/12/20 07:49:27 tsujimura543
* 輝度の表示を追加
*
* Revision 1.64 2002/12/20 06:43:32 tsujimura543
* 朔～次の朔 の表示が 1 lunation 前のものを表示してしまうことが
* ある不具合に対処
*
* Revision 1.63 2001/04/17 13:43:38 tsujimura543
* jdate() と jtime() の引数を変更 (2038年問題から解放)
*
* Revision 1.62 2001/02/22 13:31:23 tsujimura543
* 1970年1月1日以前、2038年1月19日以降の日時を指定するとmktime()で例外が発生
* する現象に対処
*
* Revision 1.61 2001/02/22 12:47:08 tsujimura543
* moon2.c を moon.c に統合。さらに、Web アプリケーションとして実運用してい
* た版と統合。
*
* Revision 1.60 2001/02/20 12:23:36 tsujimura543
* 他の派生バージョンと統合するため、いったん revision を固定
*
* Revision 1.54 2001/01/17 18:09:23 tsujimura543
* lunation の変わり目の直前になると月齢が負の値になってしまうことがある不具
* 合に対処
*
* Revision 1.53 2000/10/18 15:43:28 tsujimura543
* 月齢を表示したい年月日をコマンドラインで指定できるようにする
*
* Revision 1.52 1999/12/20 15:39:04 tsujimura543
* 実際の月齢より 約1.5 くらい大きな値になってしまう不具合に対処
*
* Revision 1.51 1999/03/29 15:53:10 tsujimura543
* moon.c の次期実験バージョン (moon2.c)
* 開発環境を Win32 に移す
* -- HTML 出力対応作業や動作確認は今後もUNIX (peach.na.rim.or.jp) 上で行なう
*
* Revision 1.1 1996/08/19 12:01:10 tsujimura
* Initial revision
* Withdrawal from `shizuka' (UNIX上での開発終了版)
*
*/
/*
A Moon for the Sun
Release 2.0
Designed and implemented by John Walker in December 1987,
revised and updated in February of 1988.
Make with:
cc -O moontool.c -o moontool -lm -lsuntool -lsunwindow -lpixrect
Adding appropriate floating point options to your hardware. This
program is a SunView tool which displays, as the icon for a closed
window, the current phase of the Moon. A subtitle in the icon gives
the age of the Moon in days and hours. If called with the "-t"
switch, it rapidly increments forward through time to display the
cycle of phases.
If you open the window, additional information is displayed regarding
the Moon. The information is generally accurate to within ten
minutes.
The algorithms used in this program to calculate the positions Sun and
Moon as seen from the Earth are given in the book "Practical Astronomy
With Your Calculator" by Peter Duffett-Smith, Second Edition,
Cambridge University Press, 1981. Ignore the word "Calculator" in the
title; this is an essential reference if you're interested in
developing software which calculates planetary positions, orbits,
eclipses, and the like. If you're interested in pursuing such
programming, you should also obtain:
"Astronomical Formulae for Calculators" by Jean Meeus, Third Edition,
Willmann-Bell, 1985. A must-have.
"Planetary Programs and Tables from -4000 to +2800" by Pierre
Bretagnon and Jean-Louis Simon, Willmann-Bell, 1986. If you want the
utmost (outside of JPL) accuracy for the planets, it's here.
"Celestial BASIC" by Eric Burgess, Revised Edition, Sybex, 1985. Very
cookbook oriented, and many of the algorithms are hard to dig out of
the turgid BASIC code, but you'll probably want it anyway.
Many of these references can be obtained from Willmann-Bell, P.O. Box
35025, Richmond, VA 23235, USA. Phone: (804) 320-7016. In addition
to their own publications, they stock most of the standard references
for mathematical and positional astronomy.
This program was written by:
John Walker
Autodesk, Inc.
2320 Marinship Way
Sausalito, CA 94965
(415) 332-2344 Ext. 829
Usenet: {sun!well}!acad!kelvin
This program is in the public domain: "Do what thou wilt shall be the
whole of the law". I'd appreciate receiving any bug fixes and/or
enhancements, which I'll incorporate in future versions of the
program. Please leave the original attribution information intact so
that credit and blame may be properly apportioned.
*/
/* Astronomical constants */
#define epoch 2444238.5 /* 1980 January 0.0 */
/* Constants defining the Sun's apparent orbit */
#define elonge 278.833540 /* Ecliptic longitude of the Sun
at epoch 1980.0 */
#define elongp 282.596403 /* Ecliptic longitude of the Sun at
perigee */
#define eccent 0.016718 /* Eccentricity of Earth's orbit */
#define sunsmax 1.495985e8 /* Semi-major axis of Earth's orbit, km */
#define sunangsiz 0.533128 /* Sun's angular size, degrees, at
semi-major axis distance */
/* Elements of the Moon's orbit, epoch 1980.0 */
#define mmlong 64.975464 /* Moon's mean lonigitude at the epoch */
#define mmlongp 349.383063 /* Mean longitude of the perigee at the
epoch */
#define mlnode 151.950429 /* Mean longitude of the node at the
epoch */
#define minc 5.145396 /* Inclination of the Moon's orbit */
#define mecc 0.054900 /* Eccentricity of the Moon's orbit */
#define mangsiz 0.5181 /* Moon's angular size at distance a
from Earth */
#define msmax 384401.0 /* Semi-major axis of Moon's orbit in km */
#define mparallax 0.9507 /* Parallax at distance a from Earth */
#define synmonth 29.53058868 /* Synodic month (new Moon to new Moon) */
#define lunatbase 2423436.0 /* Base date for E. W. Brown's numbered
series of lunations (1923 January 16) */
/* Properties of the Earth */
#define earthrad 6378.16 /* Radius of Earth in kilometres */
#ifdef WIN32
# include <windows.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <time.h>
#ifdef M_PI
# define PI M_PI
#else
# define PI 3.14159265358979323846 /* Assume not near black hole nor in
Tennessee */
#endif
/* Handy mathematical functions */
#define sgn(x) (((x) < 0) ? -1 : ((x) > 0 ? 1 : 0)) /* Extract sign */
#define abs(x) ((x) < 0 ? (-(x)) : (x)) /* Absolute val */
#define fixangle(a) ((a) - 360.0 * (floor((a) / 360.0))) /* Fix angle */
#define torad(d) ((d) * (PI / 180.0)) /* Deg->Rad */
#define todeg(d) ((d) * (180.0 / PI)) /* Rad->Deg */
#define dsin(x) (sin(torad((x)))) /* Sin from deg */
#define dcos(x) (cos(torad((x)))) /* Cos from deg */
#ifndef WIN32
# ifndef TRUE
# define TRUE 1
# define FALSE (!TRUE)
# endif
#endif
#if 0
static int testmode = FALSE; /* Rapid warp through time for debugging */
#endif
/* Forward functions */
#ifdef __STDC__
static double jtime( long, long, long, long, long, long );
static double phase( double, double *, double *, double *, double *, double *, double * );
static void phasehunt( double, double * );
static void jyear( double, long *, long *, long* );
static void jhms( double, long *, long *, long* );
#else
double jtime(), phase();
void phasehunt();
void jyear(), jhms();
#endif
/* JDATE -- Convert internal GMT date and time to Julian day
and fraction. */
static long jdate( yy, mm, dd )
long yy, mm, dd;
{
long c, m, y;
y = yy;
m = mm;
if (m > 2)
m = m - 3;
else {
m = m + 9;
y--;
}
c = y / 100L; /* Compute century */
y -= 100L * c;
return dd + (c * 146097L) / 4 + (y * 1461L) / 4 +
(m * 153L + 2) / 5 + 1721119L;
}
/* JTIME -- Convert internal GMT date and time to astronomical Julian
time (i.e. Julian date plus day fraction, expressed as
a double). */
static double jtime( yy, mm, dd, HH, MM, SS )
long yy, mm, dd, HH, MM, SS;
{
return (jdate(yy, mm, dd) - 0.5) +
(SS + 60 * (MM + 60 * HH)) / 86400.0;
}
/* JYEAR -- Convert Julian date to year, month, day, which are
returned via integer pointers to integers. */
static void jyear(td, yy, mm, dd)
double td;
long *yy, *mm, *dd;
{
double j, d, y, m;
td += 0.5; /* Astronomical to civil */
j = floor(td);
j = j - 1721119.0;
y = floor(((4 * j) - 1) / 146097.0);
j = (j * 4.0) - (1.0 + (146097.0 * y));
d = floor(j / 4.0);
j = floor(((4.0 * d) + 3.0) / 1461.0);
d = ((4.0 * d) + 3.0) - (1461.0 * j);
d = floor((d + 4.0) / 4.0);
m = floor(((5.0 * d) - 3) / 153.0);
d = (5.0 * d) - (3.0 + (153.0 * m));
d = floor((d + 5.0) / 5.0);
y = (100.0 * y) + j;
if (m < 10.0)
m = m + 3;
else {
m = m - 9;
y = y + 1;
}
*yy = (long)y;
*mm = (long)m;
*dd = (long)d;
}
/* JHMS -- Convert Julian time to hour, minutes, and seconds. */
static void jhms(j, h, m, s)
double j;
long *h, *m, *s;
{
long ij;
j += 0.5; /* Astronomical to civil */
ij = (long)((j - floor(j)) * 86400.0);
*h = ij / 3600L;
*m = (ij / 60L) % 60L;
*s = ij % 60L;
}
/* MEANPHASE -- Calculates mean phase of the Moon for a given
base date and desired phase:
0.0 New Moon
0.25 First quarter
0.5 Full moon
0.75 Last quarter
Beware!!! This routine returns meaningless
results for any other phase arguments. Don't
attempt to generalise it without understanding
that the motion of the moon is far more complicated
that this calculation reveals. */
static double meanphase(sdate, phase, usek, cnt)
double sdate, phase;
double *usek;
int *cnt;
{
long yy, mm, dd;
double k, t, t2, t3, nt1;
double preK;
static double preNt1 = 0.0;
jyear(sdate, &yy, &mm, &dd);
preK = k = (yy + ((mm - 1L) * (1.0 / 12.0)) - 1900.0) * 12.3685;
/* Time in Julian centuries from 1900 January 0.5 */
t = (sdate - 2415020.0) / 36525.64;
t2 = t * t; /* Square for frequent use */
t3 = t2 * t; /* Cube for frequent use */
*usek = k = floor(k) + phase;
nt1 = 2415020.75933 + synmonth * k
+ 0.0001178 * t2
- 0.000000155 * t3
+ 0.00033 * dsin(166.56 + 132.87 * t - 0.009173 * t2);
if ( *cnt >= 1 ) {
/* printf( "nt1 = %f, preNt1 = %f\n", nt1, preNt1 ); */
if ( nt1 - preNt1 > 45.0 ) {
*usek = k = floor(preK) - 1.0;
nt1 = 2415020.75933 + synmonth * k
+ 0.0001178 * t2
- 0.000000155 * t3
+ 0.00033 * dsin(166.56 + 132.87 * t - 0.009173 * t2);
}
}
(*cnt)++;
preNt1 = nt1;
return nt1;
}
/* TRUEPHASE -- Given a K value used to determine the
mean phase of the new moon, and a phase
selector (0.0, 0.25, 0.5, 0.75), obtain
the true, corrected phase time. */
static double truephase(k, phase)
double k, phase;
{
double t, t2, t3, pt, m, mprime, f;
int apcor = FALSE;
k += phase; /* Add phase to new moon time */
t = k / 1236.85; /* Time in Julian centuries from
1900 January 0.5 */
t2 = t * t; /* Square for frequent use */
t3 = t2 * t; /* Cube for frequent use */
pt = 2415020.75933 /* Mean time of phase */
+ synmonth * k
+ 0.0001178 * t2
- 0.000000155 * t3
+ 0.00033 * dsin(166.56 + 132.87 * t - 0.009173 * t2);
m = 359.2242 /* Sun's mean anomaly */
+ 29.10535608 * k
- 0.0000333 * t2
- 0.00000347 * t3;
mprime = 306.0253 /* Moon's mean anomaly */
+ 385.81691806 * k
+ 0.0107306 * t2
+ 0.00001236 * t3;
f = 21.2964 /* Moon's argument of latitude */
+ 390.67050646 * k
- 0.0016528 * t2
- 0.00000239 * t3;
if ((phase < 0.01) || (abs(phase - 0.5) < 0.01)) {
/* Corrections for New and Full Moon */
pt += (0.1734 - 0.000393 * t) * dsin(m)
+ 0.0021 * dsin(2 * m)
- 0.4068 * dsin(mprime)
+ 0.0161 * dsin(2 * mprime)
- 0.0004 * dsin(3 * mprime)
+ 0.0104 * dsin(2 * f)
- 0.0051 * dsin(m + mprime)
- 0.0074 * dsin(m - mprime)
+ 0.0004 * dsin(2 * f + m)
- 0.0004 * dsin(2 * f - m)
- 0.0006 * dsin(2 * f + mprime)
+ 0.0010 * dsin(2 * f - mprime)
+ 0.0005 * dsin(m + 2 * mprime);
apcor = TRUE;
}
else if ((abs(phase - 0.25) < 0.01 || (abs(phase - 0.75) < 0.01))) {
pt += (0.1721 - 0.0004 * t) * dsin(m)
+ 0.0021 * dsin(2 * m)
- 0.6280 * dsin(mprime)
+ 0.0089 * dsin(2 * mprime)
- 0.0004 * dsin(3 * mprime)
+ 0.0079 * dsin(2 * f)
- 0.0119 * dsin(m + mprime)
- 0.0047 * dsin(m - mprime)
+ 0.0003 * dsin(2 * f + m)
- 0.0004 * dsin(2 * f - m)
- 0.0006 * dsin(2 * f + mprime)
+ 0.0021 * dsin(2 * f - mprime)
+ 0.0003 * dsin(m + 2 * mprime)
+ 0.0004 * dsin(m - 2 * mprime)
- 0.0003 * dsin(2 * m + mprime);
if (phase < 0.5)
/* First quarter correction */
pt += 0.0028 - 0.0004 * dcos(m) + 0.0003 * dcos(mprime);
else
/* Last quarter correction */
pt += -0.0028 + 0.0004 * dcos(m) - 0.0003 * dcos(mprime);
apcor = TRUE;
}
if (!apcor) {
fprintf(stderr, "TRUEPHASE called with invalid phase selector.\n");
abort();
}
return pt;
}
/* PHASEHUNT -- Find time of phases of the moon which surround
the current date. Five phases are found, starting
and ending with the new moons which bound the
current lunation. */
static void phasehunt(sdate, phases)
double sdate;
double phases[5];
{
double adate, k1, k2, nt1, nt2;
int cnt = 0;
adate = sdate - 45.0;
nt1 = meanphase(adate, 0.0, &k1, &cnt);
while (TRUE) {
adate += synmonth;
nt2 = meanphase(adate, 0.0, &k2, &cnt);
if ((nt1 <= sdate) && (nt2 > sdate))
break;
nt1 = nt2;
k1 = k2;
}
if (k2 - k1 >= 2.0)
k2 = k1 + 1.0;
phases[0] = truephase(k1, 0.0);
phases[1] = truephase(k1, 0.25);
phases[2] = truephase(k1, 0.5);
phases[3] = truephase(k1, 0.75);
phases[4] = truephase(k2, 0.0);
}
/* KEPLER -- Solve the equation of Kepler. */
static double kepler(m, ecc)
double m, ecc;
{
double e, delta;
#define EPSILON 1E-6
e = m = torad(m);
do {
delta = e - ecc * sin(e) - m;
e -= delta / (1 - ecc * cos(e));
} while (abs(delta) > EPSILON);
return e;
}
/* PHASE -- Calculate phase of moon as a fraction:
The argument is the time for which the phase is requested,
expressed as a Julian date and fraction. Returns the terminator
phase angle as a percentage of a full circle (i.e., 0 to 1),
and stores into pointer arguments the illuminated fraction of
the Moon's disc, the Moon's age in days and fraction, the
distance of the Moon from the centre of the Earth, and the
angular diameter subtended by the Moon as seen by an observer
at the centre of the Earth.
*/
static double phase(pdate, pphase, mage, dist, angdia, sudist, suangdia)
double pdate;
double *pphase; /* Illuminated fraction */
double *mage; /* Age of moon in days */
double *dist; /* Distance in kilometres */
double *angdia; /* Angular diameter in degrees */
double *sudist; /* Distance to Sun */
double *suangdia; /* Sun's angular diameter */
{
double Day, N, M, Ec, Lambdasun, ml, MM, MN, Ev, Ae, A3, MmP,
mEc, A4, lP, V, lPP, NP, y, x, Lambdamoon,
MoonAge, MoonPhase,
MoonDist, MoonDFrac, MoonAng,
F, SunDist, SunAng;
/* Calculation of the Sun's position */
Day = pdate - epoch; /* Date within epoch */
N = fixangle((360.0 / 365.2422) * Day); /* Mean anomaly of the Sun */
M = fixangle(N + elonge - elongp); /* Convert from perigee
co-ordinates to epoch 1980.0 */
Ec = kepler(M, eccent); /* Solve equation of Kepler */
Ec = sqrt((1.0 + eccent) / (1.0 - eccent)) * tan(Ec / 2.0);
Ec = 2.0 * todeg(atan(Ec)); /* True anomaly */
Lambdasun = fixangle(Ec + elongp); /* Sun's geocentric ecliptic
longitude */
/* Orbital distance factor */
F = ((1.0 + eccent * cos(torad(Ec))) / (1.0 - eccent * eccent));
SunDist = sunsmax / F; /* Distance to Sun in km */
SunAng = F * sunangsiz; /* Sun's angular size in degrees */
/* Calculation of the Moon's position */
/* Moon's mean longitude */
ml = fixangle(13.1763966 * Day + mmlong);
/* Moon's mean anomaly */
MM = fixangle(ml - 0.1114041 * Day - mmlongp);
/* Moon's ascending node mean longitude */
MN = fixangle(mlnode - 0.0529539 * Day);
/* Evection */
Ev = 1.2739 * sin(torad(2.0 * (ml - Lambdasun) - MM));
/* Annual equation */
Ae = 0.1858 * sin(torad(M));
/* Correction term */
A3 = 0.37 * sin(torad(M));
/* Corrected anomaly */
MmP = MM + Ev - Ae - A3;
/* Correction for the equation of the centre */
mEc = 6.2886 * sin(torad(MmP));
/* Another correction term */
A4 = 0.214 * sin(torad(2.0 * MmP));
/* Corrected longitude */
lP = ml + Ev + mEc - Ae + A4;
/* Variation */
V = 0.6583 * sin(torad(2.0 * (lP - Lambdasun)));
/* True longitude */
lPP = lP + V;
/* Corrected longitude of the node */
NP = MN - 0.16 * sin(torad(M));
/* Y inclination coordinate */
y = sin(torad(lPP - NP)) * cos(torad(minc));
/* X inclination coordinate */
x = cos(torad(lPP - NP));
/* Ecliptic longitude */
Lambdamoon = todeg(atan2(y, x));
Lambdamoon += NP;
#if 0
/* Ecliptic latitude */
(void)todeg(asin(sin(torad(lPP - NP)) * sin(torad(minc))));
#endif
/* Calculation of the phase of the Moon */
/* Age of the Moon in degrees */
MoonAge = lPP - Lambdasun;
/* Phase of the Moon */
MoonPhase = (1.0 - cos(torad(MoonAge))) / 2.0;
/* Calculate distance of moon from the centre of the Earth */
MoonDist = (msmax * (1.0 - mecc * mecc)) /
(1.0 + mecc * cos(torad(MmP + mEc)));
/* Calculate Moon's angular diameter */
MoonDFrac = MoonDist / msmax;
MoonAng = mangsiz / MoonDFrac;
#if 0
/* Calculate Moon's parallax */
MoonPar = mparallax / MoonDFrac;
#endif
*pphase = MoonPhase;
*mage = synmonth * (fixangle(MoonAge) / 360.0);
*dist = MoonDist;
*angdia = MoonAng;
*sudist = SunDist;
*suangdia = SunAng;
return fixangle(MoonAge) / 360.0;
}
/*** qpom2() is arranged from qpom(). qpom() is written by Christopher Osburn.
/*
** qpom.c
** Christopher Osburn 911102
**
** Routines returning age of the moon (qpom), quantity of lunar face
** under illumination (illum), and the current lunation number
** (lunation) using the extremely cheesy epoch/iteration method.
**
*/
#define LPERIOD ((double)2551442.9) /* synodic period of the moon, seconds,
from astronomical almanac 1992 */
#ifdef __STDC__
double qpom2(time_t now, time_t epoch_near)
#else
double qpom2(now, epoch_near)
time_t now, epoch_near;
#endif
{
double diff, howfar;
diff = (double) now - epoch_near;
/* 本家の qpom() は epoch_near の部分に固定値を使用している
* ため、lunation の進行に伴って誤差がどんどん増えていくとい
* う欠点がある(実際に、qpom.c は数年毎に固定値部分を変更す
* る修正版が出ている)。
* qpom2() では、固定値ではなく、直近の epoch (朔のユリウス
* 日)を算出し、使用することで、長期にわたってプログラム変
* 更せずに済ませることができるものを目指している。
*/
howfar = diff / LPERIOD;
return LPERIOD * (howfar - (int) howfar) / 86400.0;
}
/*
* phasehunt() で求めた朔、上弦、望、下弦、次の朔の日時を
* qpom2() の第1引数に指定した場合の月齢が 0.0, 7.5, 15.0,
* 22.5, 30.0 にはならない(月齢計算の方法が違う方式のため)
* 以下の関数は、qpom2() の値が 0.0, 7.5, 15.0, 22.5, 30.0
* になる日時を求めるためのものである。
*/
#ifdef __STDC__
struct tm *
getTruePhaseWithQpom( time_t t1, time_t t2, double curAom, double moonPhase )
#else
struct tm *
getTruePhaseWithQpom( t1, t2, curAom, moonPhase )
time_t t1;
time_t t2;
double curAom;
double moonPhase;
#endif
{
time_t t;
double aom, diff;
struct tm *tm;
diff = moonPhase - curAom;
t = t1 + (int)(diff * 24.0 * 60.0 * 60.0);
aom = qpom2( t, t2 );
if ( aom > moonPhase ) {
t -= (int)((aom - moonPhase) * 24.0 * 60.0 * 60.0);
aom = qpom2( t, t2 );
}
tm = gmtime( &t );
return ( tm );
}
#ifdef __STDC__
void
getPhasesWithQpom(
time_t t1, time_t t2, double curAom, /*long lunation,*/ char flag )
#else
getPhasesWithQpom( t1, t2, curAom, /*lunation,*/ flag )
time_t t1;
time_t t2;
double curAom;
/*long lunation;*/
char flag;
#endif
{
struct tm *tm;
if ( (flag & 2) == 0 ) {
return;
}
if ( (flag & 1) == 1 )
printf( "<TR><TD COLSPAN=2>" );
printf( "\n参考: \n" );
if ( (flag & 1) == 1 )
printf( "</TD></TR>\n<TR><TD ALIGN=\"RIGHT\">" );
tm = getTruePhaseWithQpom( t1, t2, curAom, synmonth * 0.00 );
printf(
/*" 朔%s %d年%02d月%02d日 %02d時%02d分 UTC (Lunation %d)\n",*/
" 朔%s %d年%02d月%02d日 %02d時%02d分 UTC\n",
(flag & 1) == 1 ? "</TD><TD COLSPAN=2>" : ":",
tm->tm_year + 1900, tm->tm_mon + 1,
tm->tm_mday, tm->tm_hour, tm->tm_min /*,
lunation*/ );
if ( (flag & 1) == 1 )
printf( "</TD></TR>\n<TR><TD ALIGN=\"RIGHT\">" );
tm = getTruePhaseWithQpom( t1, t2, curAom, synmonth * 0.25 );
printf( " 上弦%s %d年%02d月%02d日 %02d時%02d分 UTC\n",
(flag & 1) == 1 ? "</TD><TD COLSPAN=2>" : ":",
tm->tm_year + 1900, tm->tm_mon + 1,
tm->tm_mday, tm->tm_hour, tm->tm_min );
if ( (flag & 1) == 1 )
printf( "</TD></TR>\n<TR><TD ALIGN=\"RIGHT\">" );
tm = getTruePhaseWithQpom( t1, t2, curAom, synmonth * 0.50 );
printf( " 望%s %d年%02d月%02d日 %02d時%02d分 UTC\n",
(flag & 1) == 1 ? "</TD><TD COLSPAN=2>" : ":",
tm->tm_year + 1900, tm->tm_mon + 1,
tm->tm_mday, tm->tm_hour, tm->tm_min );
if ( (flag & 1) == 1 )
printf( "</TD></TR>\n<TR><TD ALIGN=\"RIGHT\">" );
tm = getTruePhaseWithQpom( t1, t2, curAom, synmonth * 0.75 );
printf( " 下弦%s %d年%02d月%02d日 %02d時%02d分 UTC\n",
(flag & 1) == 1 ? "</TD><TD COLSPAN=2>" : ":",
tm->tm_year + 1900, tm->tm_mon + 1,
tm->tm_mday, tm->tm_hour, tm->tm_min );
if ( (flag & 1) == 1 )
printf( "</TD></TR>\n<TR><TD ALIGN=\"RIGHT\">" );
tm = getTruePhaseWithQpom( t1, t2, curAom, synmonth * 1.00 );
printf(
/*" 次の朔%s %d年%02d月%02d日 %02d時%02d分 UTC (Lunation %d)\n",*/
" 次の朔%s %d年%02d月%02d日 %02d時%02d分 UTC\n",
(flag & 1) == 1 ? "</TD><TD COLSPAN=2>" : ":",
tm->tm_year + 1900, tm->tm_mon + 1,
tm->tm_mday, tm->tm_hour, tm->tm_min /*,
lunation + 1*/ );
if ( (flag & 1) == 1 )
printf( "</TD></TR>\n" );
}
#ifdef UNIX
#ifdef SYSV
#define _tzname tzname
#define _timezone timezone
#else
char *_tzname[2];
long _timezone;
#endif
#endif
time_t
getTargetDateTime( argc, argv, flag )
int argc;
char *argv[];
char *flag;
{
struct tm _tm;
time_t t = 0;
/* *flag = 0; */
if ( argc > 1 ) {
int i, j;
for ( i = 1; i < argc; i++ ) {
if ( argv[i][0] == '-' ) {
for ( j = 1; argv[i][j] != '\0'; j++ ) {
switch ( argv[i][j] ) {
case 'H':
*flag |= 1;
break;
case 'v':
*flag |= 2;
break;
}
}
continue;
}
else if ( (argv[i][0] >= '0') && (argv[i][0] <= '9') &&
( (strlen( argv[i] ) == 8) ||
(strlen( argv[i] ) == 12) ||
(strlen( argv[i] ) == 14) ) ) {
int y, m, d, H = 0, M = 0, S = 0;
y = (argv[i][0] - '0') * 1000 +
(argv[i][1] - '0') * 100 +
(argv[i][2] - '0') * 10 +
(argv[i][3] - '0');
m = (argv[i][4] - '0') * 10 + (argv[i][5] - '0');
d = (argv[i][6] - '0') * 10 + (argv[i][7] - '0');
if ( argv[i][8] != '\0' ) {
H = (argv[i][ 8] - '0') * 10 + (argv[i][ 9] - '0');
M = (argv[i][10] - '0') * 10 + (argv[i][11] - '0');
if ( argv[i][12] != '\0' ) {
S = (argv[i][12] - '0') * 10 + (argv[i][13] - '0');
}
}
if ( y < 1970 ) {
fprintf( stderr,
"1970年以前の月齢計算はサポートしていません。\n" );
exit( 1 );
}
if ( (y == 1970) && (m == 1) && (d == 1) && (H < 9) ) {
fprintf( stderr, "%s%s\n",
"1970年1月1日の午前9時(日本時間)以前の",
"月齢計算はサポートしていません。" );
fprintf( stderr, "%s%s\n",
"代わりに、1970年1月1日の午前9時0分1秒",
"(日本時間)の月齢を表示します。" );
H = 9; M = 0; S = 1;
}
if ( y > 2038 ) {
fprintf( stderr,
"2038年以降の月齢計算はサポートしていません。\n" );
exit( 1 );
}
if ( (y == 2038) &&
( (m > 1) ||
((m == 1) &&
( (d > 19) ||
((d == 19) &&
( (H > 3) ||
((H == 3) &&
( (M > 14) ||
((M == 14) && (S >= 8))
)
)
)
)
)
)
) ) {
fprintf( stderr, "%s%s\n",
"2038年1月19日の午前3時14分8秒(日本時間)以降の",
"月齢計算はサポートしていません。" );
fprintf( stderr, "%s%s\n",
"代わりに、2038年1月19日の午前3時14分7秒",
"を(日本時間)の月齢表示します。" );
m = 1; d = 19;
H = 3; M = 14; S = 7;
}
memset( &_tm, 0, sizeof ( struct tm ) );
_tm.tm_year = y - 1900;
_tm.tm_mon = m - 1;
_tm.tm_mday = d;
_tm.tm_hour = H;
_tm.tm_min = M;
_tm.tm_sec = S;
t = mktime( &_tm );
}
else if ( !strcmp( argv[i], "yesterday" ) ) {
t = time( NULL ) - 24 * 60 * 60;
}
else if ( !strcmp( argv[i], "tomorrow" ) ) {
t = time( NULL ) + 24 * 60 * 60;
}
}
}
if ( t == 0 )
t = time( NULL );
return ( t );
}
#ifndef NUL
#define NUL '\0'
#endif
#ifdef __STDC__
char *decodeURL( const char *pp );
#else
char *decodeURL();
#endif
static void
setParameter( p, yy, mm, dd, HH, MM, SS )
char *p;
int *yy, *mm, *dd, *HH, *MM, *SS;
{
char *q, *r;
char buf[BUFSIZ];
while ( *p ) {
q = NULL;
if ( !strncmp( p, "y=", 2 ) ) {
p += 2;
q = &(buf[0]);
while ( *p && (*p != '&') )
*q++ = *p++;
*q = NUL;
if ( *p == '&' )
p++;
r = decodeURL( buf );
if ( (*r >= '0') && (*r <= '9') )
*yy = atoi( r );
}
if ( !strncmp( p, "m=", 2 ) ) {
p += 2;
q = &(buf[0]);
while ( *p && (*p != '&') )
*q++ = *p++;
*q = NUL;
if ( *p == '&' )
p++;
r = decodeURL( buf );
if ( (*r >= '0') && (*r <= '9') )
*mm = atoi( r );
}
if ( !strncmp( p, "d=", 2 ) ) {
p += 2;
q = &(buf[0]);
while ( *p && (*p != '&') )
*q++ = *p++;
*q = NUL;
if ( *p == '&' )
p++;
r = decodeURL( buf );
if ( (*r >= '0') && (*r <= '9') )
*dd = atoi( r );
}
if ( !strncmp( p, "H=", 2 ) ) {
p += 2;
q = &(buf[0]);
while ( *p && (*p != '&') )
*q++ = *p++;
*q = NUL;
if ( *p == '&' )
p++;
r = decodeURL( buf );
if ( (*r >= '0') && (*r <= '9') ) {
*HH = atoi( r );
}
}
if ( !strncmp( p, "M=", 2 ) ) {
p += 2;
q = &(buf[0]);
while ( *p && (*p != '&') )
*q++ = *p++;
*q = NUL;
if ( *p == '&' )
p++;
r = decodeURL( buf );
if ( (*r >= '0') && (*r <= '9') ) {
*MM = atoi( r );
}
}
if ( !strncmp( p, "S=", 2 ) ) {
p += 2;
q = &(buf[0]);
while ( *p && (*p != '&') )
*q++ = *p++;
*q = NUL;
if ( *p == '&' )
p++;
r = decodeURL( buf );
if ( (*r >= '0') && (*r <= '9') ) {
*SS = atoi( r );
}
}
if ( !q )
p++;
}
}
static int
isLeapYear( yy )