1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
# date.rb: Written by Tadayoshi Funaba 1998
# $Id: date.rb,v 1.3 1998/03/08 09:43:54 tadf Exp $
class Date
include Comparable
MONTHNAMES = [ '', 'January', 'February', 'March', 'April', 'May', 'June',
'July', 'August', 'September', 'October', 'November', 'December' ]
DAYNAMES = [ 'Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday',
'Friday', 'Saturday' ]
GREGORY = 2299161 # Oct 15, 1582
ENGLAND = 2361222 # Sept 14, 1752
def Date.civil_to_jd(y, m, d, gs = true)
if m <= 2 then
y -= 1
m += 12
end
a = (y / 100).to_i
b = (a / 4).to_i
c = 2 - a + b
e = (365.25 * (y + 4716)).to_i
f = (30.6001 * (m + 1)).to_i
jd = c + d + e + f - 1524
unless
(if gs.kind_of? Numeric then jd >= gs else gs end) then
jd -= c
end
return jd
end
def Date.jd_to_civil(jd, gs = true)
unless
(if gs.kind_of? Numeric then jd >= gs else gs end) then
a = jd
else
w = ((jd - 1867216.25) / 36524.25).to_i
x = (w / 4).to_i
a = jd + 1 + w - x
end
b = a + 1524
c = ((b - 122.1) / 365.25).to_i
d = (365.25 * c).to_i
e = ((b - d) / 30.6001).to_i
f = (30.6001 * e).to_i
day = b - d - f
if e <= 13 then
m = e - 1
else
m = e - 13
end
if m <= 2 then
y = c - 4715
else
y = c - 4716
end
return y, m, day
end
def Date.mjd_to_jd(mjd)
mjd + 2400000.5
end
def Date.jd_to_mjd(jd)
jd - 2400000.5
end
def Date.tjd_to_jd(tjd)
tjd + 2440000.5
end
def Date.jd_to_tjd(jd)
jd - 2440000.5
end
def initialize(jd = 0, gs = GREGORY)
@jd = jd
@gs = gs
end
def Date.new3(y = -4712, m = 1, d = 1, gs = GREGORY)
jd = Date.civil_to_jd(y, m, d, gs)
y2, m2, d2 = Date.jd_to_civil(jd, gs)
unless y == y2 and m == m2 and d == d2 then
raise ArgumentError, 'invalid date'
end
Date.new(jd, gs)
end
def Date.today(gs = GREGORY)
Date.new3(*(Time.now.to_a[3..5].reverse << gs))
end
def jd
@jd
end
def mjd
Date.jd_to_mjd(@jd)
end
def tjd
Date.jd_to_tjd(@jd)
end
def year
Date.jd_to_civil(@jd, @gs)[0]
end
def yday
gs = if @gs.kind_of? Numeric then @jd >= @gs else @gs end
jd = Date.civil_to_jd(year - 1, 12, 31, gs)
@jd - jd
end
def mon
Date.jd_to_civil(@jd, @gs)[1]
end
def mday
Date.jd_to_civil(@jd, @gs)[2]
end
def wday
k = (@jd + 1) % 7
k += 7 if k < 0
k
end
def leap?
gs = if @gs.kind_of? Numeric then @jd >= @gs else @gs end
jd = Date.civil_to_jd(year, 2, 28, gs)
Date.jd_to_civil(jd + 1, gs)[1] == 2
end
def + (other)
if other.kind_of? Numeric then
return Date.new(@jd + other, @gs)
end
raise TypeError, 'expected numeric'
end
def - (other)
if other.kind_of? Numeric then
return Date.new(@jd - other, @gs)
elsif other.kind_of? Date then
return @jd - other.jd
end
raise TypeError, 'expected numeric or date'
end
def <=> (other)
if other.kind_of? Numeric then
return @jd <=> other
elsif other.kind_of? Date then
return @jd <=> other.jd
end
raise TypeError, 'expected numeric or date'
end
def downto(min)
@jd.downto(min.jd) do |jd|
yield Date.new(jd, @gs)
end
end
def upto(max)
@jd.upto(max.jd) do |jd|
yield Date.new(jd, @gs)
end
end
def step(max, step)
@jd.step(max.jd, step) do |jd|
yield Date.new(jd, @gs)
end
end
def eql? (other)
self == other
end
def hash
@jd
end
def to_s
format('%04d-%02d-%02d', *Date.jd_to_civil(@jd, @gs))
end
end
|