(chinese-calendar-celestial-stem, chinese-calendar-terrestrial-branch):
[emacs.git] / lisp / calendar / cal-china.el
blobc46f8bfc9eb31508511e06435b3af65e44146c74
1 ;;; cal-china.el --- calendar functions for the Chinese calendar
3 ;; Copyright (C) 1995, 1997, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
4 ;; 2008 Free Software Foundation, Inc.
6 ;; Author: Edward M. Reingold <reingold@cs.uiuc.edu>
7 ;; Maintainer: Glenn Morris <rgm@gnu.org>
8 ;; Keywords: calendar
9 ;; Human-Keywords: Chinese calendar, calendar, holidays, diary
11 ;; This file is part of GNU Emacs.
13 ;; GNU Emacs is free software; you can redistribute it and/or modify
14 ;; it under the terms of the GNU General Public License as published by
15 ;; the Free Software Foundation; either version 3, or (at your option)
16 ;; any later version.
18 ;; GNU Emacs is distributed in the hope that it will be useful,
19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 ;; GNU General Public License for more details.
23 ;; You should have received a copy of the GNU General Public License
24 ;; along with GNU Emacs; see the file COPYING. If not, write to the
25 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
26 ;; Boston, MA 02110-1301, USA.
28 ;;; Commentary:
30 ;; This collection of functions implements the features of calendar.el,
31 ;; diary.el, and holidays.el that deal with the Chinese calendar. The rules
32 ;; used for the Chinese calendar are those of Baolin Liu (see L. E. Doggett's
33 ;; article "Calendars" in the Explanatory Supplement to the Astronomical
34 ;; Almanac, second edition, 1992) for the calendar as revised at the beginning
35 ;; of the Qing dynasty in 1644. The nature of the astronomical calculations
36 ;; is such that precise calculations cannot be made without great expense in
37 ;; time, so that the calendars produced may not agree perfectly with published
38 ;; tables--but no two pairs of published tables agree perfectly either! Liu's
39 ;; rules produce a calendar for 2033 which is not accepted by all authorities.
40 ;; The date of Chinese New Year is correct from 1644-2051.
42 ;; Technical details of all the calendrical calculations can be found in
43 ;; ``Calendrical Calculations: The Millennium Edition'' by Edward M. Reingold
44 ;; and Nachum Dershowitz, Cambridge University Press (2001).
46 ;; Note to maintainers:
47 ;; Use `chinese-year-cache-init' every few years to recenter the default
48 ;; value of `chinese-year-cache'.
50 ;;; Code:
52 (require 'lunar)
54 (defgroup chinese-calendar nil
55 "Chinese calendar support."
56 :group 'calendar)
58 (defcustom chinese-calendar-time-zone
59 '(if (< year 1928)
60 (+ 465 (/ 40.0 60.0))
61 480)
62 "Minutes difference between local standard time for Chinese calendar and UTC.
63 Default is for Beijing. This is an expression in `year' since it changed at
64 1928-01-01 00:00:00 from UT+7:45:40 to UT+8."
65 :type 'sexp
66 :group 'chinese-calendar)
68 (defcustom chinese-calendar-location-name "Beijing"
69 "Name of location used for calculation of Chinese calendar."
70 :type 'string
71 :group 'chinese-calendar)
73 (defcustom chinese-calendar-daylight-time-offset 0
74 ;; The correct value is as follows, but the Chinese calendrical
75 ;; authorities do NOT use DST in determining astronomical events:
76 ;; 60
77 "Minutes difference between daylight saving and standard time.
78 Default is for no daylight saving time."
79 :type 'integer
80 :group 'chinese-calendar)
82 (defcustom chinese-calendar-standard-time-zone-name
83 '(if (< year 1928)
84 "PMT"
85 "CST")
86 "Abbreviated name of standard time zone used for Chinese calendar.
87 This is an expression depending on `year' because it changed
88 at 1928-01-01 00:00:00 from `PMT' to `CST'."
89 :type 'sexp
90 :group 'chinese-calendar)
92 (defcustom chinese-calendar-daylight-time-zone-name "CDT"
93 "Abbreviated name of daylight saving time zone used for Chinese calendar."
94 :type 'string
95 :group 'chinese-calendar)
97 (defcustom chinese-calendar-daylight-savings-starts nil
98 ;; The correct value is as follows, but the Chinese calendrical
99 ;; authorities do NOT use DST in determining astronomical events:
100 ;; '(cond ((< 1986 year) (calendar-nth-named-day 1 0 4 year 10))
101 ;; ((= 1986 year) '(5 4 1986))
102 ;; (t nil))
103 "Sexp giving the date on which daylight saving time starts.
104 Default is for no daylight saving time. See documentation of
105 `calendar-daylight-savings-starts'."
106 :type 'sexp
107 :group 'chinese-calendar)
109 (defcustom chinese-calendar-daylight-savings-ends nil
110 ;; The correct value is as follows, but the Chinese calendrical
111 ;; authorities do NOT use DST in determining astronomical events:
112 ;; '(if (<= 1986 year) (calendar-nth-named-day 1 0 9 year 11))
113 "Sexp giving the date on which daylight saving time ends.
114 Default is for no daylight saving time. See documentation of
115 `calendar-daylight-savings-ends'."
116 :type 'sexp
117 :group 'chinese-calendar)
119 (defcustom chinese-calendar-daylight-savings-starts-time 0
120 "Number of minutes after midnight that daylight saving time starts.
121 Default is for no daylight saving time."
122 :type 'integer
123 :group 'chinese-calendar)
125 (defcustom chinese-calendar-daylight-savings-ends-time 0
126 "Number of minutes after midnight that daylight saving time ends.
127 Default is for no daylight saving time."
128 :type 'integer
129 :group 'chinese-calendar)
131 (defcustom chinese-calendar-celestial-stem
132 ["Jia" "Yi" "Bing" "Ding" "Wu" "Ji" "Geng" "Xin" "Ren" "Gui"]
133 "Prefixes used by `calendar-chinese-sexagesimal-name'."
134 :group 'chinese-calendar
135 :type '(vector (string :tag "Jia")
136 (string :tag "Yi")
137 (string :tag "Bing")
138 (string :tag "Ding")
139 (string :tag "Wu")
140 (string :tag "Ji")
141 (string :tag "Geng")
142 (string :tag "Xin")
143 (string :tag "Ren")
144 (string :tag "Gui")))
146 (defcustom chinese-calendar-terrestrial-branch
147 ["Zi" "Chou" "Yin" "Mao" "Chen" "Si" "Wu" "Wei" "Shen" "You" "Xu" "Hai"]
148 "Suffixes used by `calendar-chinese-sexagesimal-name'."
149 :group 'chinese-calendar
150 :type '(vector (string :tag "Zi")
151 (string :tag "Chou")
152 (string :tag "Yin")
153 (string :tag "Mao")
154 (string :tag "Chen")
155 (string :tag "Si")
156 (string :tag "Wu")
157 (string :tag "Wei")
158 (string :tag "Shen")
159 (string :tag "You")
160 (string :tag "Xu")
161 (string :tag "Hai")))
163 ;;; End of user options.
166 (defun calendar-chinese-sexagesimal-name (n)
167 "The N-th name of the Chinese sexagesimal cycle.
168 N congruent to 1 gives the first name, N congruent to 2 gives the second name,
169 ..., N congruent to 60 gives the sixtieth name."
170 (format "%s-%s"
171 (aref chinese-calendar-celestial-stem (% (1- n) 10))
172 (aref chinese-calendar-terrestrial-branch (% (1- n) 12))))
174 (defun chinese-zodiac-sign-on-or-after (d)
175 "Absolute date of first new Zodiac sign on or after absolute date D.
176 The Zodiac signs begin when the sun's longitude is a multiple of 30 degrees."
177 (let* ((year (extract-calendar-year (calendar-gregorian-from-absolute d)))
178 (calendar-time-zone (eval chinese-calendar-time-zone)) ; uses year
179 (calendar-daylight-time-offset
180 chinese-calendar-daylight-time-offset)
181 (calendar-standard-time-zone-name
182 chinese-calendar-standard-time-zone-name)
183 (calendar-daylight-time-zone-name
184 chinese-calendar-daylight-time-zone-name)
185 (calendar-calendar-daylight-savings-starts
186 chinese-calendar-daylight-savings-starts)
187 (calendar-daylight-savings-ends
188 chinese-calendar-daylight-savings-ends)
189 (calendar-daylight-savings-starts-time
190 chinese-calendar-daylight-savings-starts-time)
191 (calendar-daylight-savings-ends-time
192 chinese-calendar-daylight-savings-ends-time))
193 (floor
194 (calendar-absolute-from-astro
195 (solar-date-next-longitude (calendar-astro-from-absolute d) 30)))))
197 (defun chinese-new-moon-on-or-after (d)
198 "Absolute date of first new moon on or after absolute date D."
199 (let* ((year (extract-calendar-year (calendar-gregorian-from-absolute d)))
200 (calendar-time-zone (eval chinese-calendar-time-zone))
201 (calendar-daylight-time-offset
202 chinese-calendar-daylight-time-offset)
203 (calendar-standard-time-zone-name
204 chinese-calendar-standard-time-zone-name)
205 (calendar-daylight-time-zone-name
206 chinese-calendar-daylight-time-zone-name)
207 (calendar-calendar-daylight-savings-starts
208 chinese-calendar-daylight-savings-starts)
209 (calendar-daylight-savings-ends
210 chinese-calendar-daylight-savings-ends)
211 (calendar-daylight-savings-starts-time
212 chinese-calendar-daylight-savings-starts-time)
213 (calendar-daylight-savings-ends-time
214 chinese-calendar-daylight-savings-ends-time))
215 (floor
216 (calendar-absolute-from-astro
217 (lunar-new-moon-on-or-after (calendar-astro-from-absolute d))))))
219 (defun chinese-month-list (start end)
220 "List of starting dates of Chinese months from START to END."
221 (if (<= start end)
222 (let ((new-moon (chinese-new-moon-on-or-after start)))
223 (if (<= new-moon end)
224 (cons new-moon
225 (chinese-month-list (1+ new-moon) end))))))
227 (defun number-chinese-months (list start)
228 "Assign month numbers to the lunar months in LIST, starting with START.
229 Numbers are assigned sequentially, START, START+1, ..., 11, with
230 half numbers used for leap months. First and last months of list
231 are never leap months."
232 (when list
233 (cons (list start (car list)) ; first month
234 ;; Remaining months.
235 (if (zerop (- 12 start (length list)))
236 ;; List is too short for a leap month.
237 (number-chinese-months (cdr list) (1+ start))
238 (if (and (cddr list) ; at least two more months...
239 (<= (nth 2 list)
240 (chinese-zodiac-sign-on-or-after (cadr list))))
241 ;; Next month is a leap month.
242 (cons (list (+ start 0.5) (cadr list))
243 (number-chinese-months (cddr list) (1+ start)))
244 ;; Next month is not a leap month.
245 (number-chinese-months (cdr list) (1+ start)))))))
247 (defun compute-chinese-year (y)
248 "Compute the structure of the Chinese year for Gregorian year Y.
249 The result is a list of pairs (i d), where month i begins on absolute date d,
250 of the Chinese months from the Chinese month following the solstice in
251 Gregorian year Y-1 to the Chinese month of the solstice of Gregorian year Y."
252 (let* ((next-solstice (chinese-zodiac-sign-on-or-after
253 (calendar-absolute-from-gregorian
254 (list 12 15 y))))
255 (list (chinese-month-list (1+ (chinese-zodiac-sign-on-or-after
256 (calendar-absolute-from-gregorian
257 (list 12 15 (1- y)))))
258 next-solstice))
259 (next-sign (chinese-zodiac-sign-on-or-after (car list))))
260 (if (= (length list) 12)
261 ;; No room for a leap month, just number them 12, 1, 2, ..., 11.
262 (cons (list 12 (car list))
263 (number-chinese-months (cdr list) 1))
264 ;; Now we can assign numbers to the list for y.
265 ;; The first month or two are special.
266 (if (or (> (car list) next-sign) (>= next-sign (cadr list)))
267 ;; First month on list is a leap month, second is not.
268 (append (list (list 11.5 (car list))
269 (list 12 (cadr list)))
270 (number-chinese-months (cddr list) 1))
271 ;; First month on list is not a leap month.
272 (append (list (list 12 (car list)))
273 (if (>= (chinese-zodiac-sign-on-or-after (cadr list))
274 (nth 2 list))
275 ;; Second month on list is a leap month.
276 (cons (list 12.5 (cadr list))
277 (number-chinese-months (cddr list) 1))
278 ;; Second month on list is not a leap month.
279 (number-chinese-months (cdr list) 1)))))))
281 (defvar chinese-year-cache
282 ;; Maintainers: delete existing value, position point at start of
283 ;; empty line, then call M-: (chinese-year-cache-init N)
284 '((2000 (12 730126) (1 730155) (2 730185) (3 730215) (4 730244) (5 730273)
285 (6 730303) (7 730332) (8 730361) (9 730391) (10 730420) (11 730450))
286 (2001 (12 730480) (1 730509) (2 730539) (3 730569) (4 730598) (4.5 730628)
287 (5 730657) (6 730687) (7 730716) (8 730745) (9 730775) (10 730804)
288 (11 730834))
289 (2002 (12 730863) (1 730893) (2 730923) (3 730953) (4 730982) (5 731012)
290 (6 731041) (7 731071) (8 731100) (9 731129) (10 731159) (11 731188))
291 (2003 (12 731218) (1 731247) (2 731277) (3 731307) (4 731336) (5 731366)
292 (6 731396) (7 731425) (8 731455) (9 731484) (10 731513) (11 731543))
293 (2004 (12 731572) (1 731602) (2 731631) (2.5 731661) (3 731690) (4 731720)
294 (5 731750) (6 731779) (7 731809) (8 731838) (9 731868) (10 731897)
295 (11 731927))
296 (2005 (12 731956) (1 731986) (2 732015) (3 732045) (4 732074) (5 732104)
297 (6 732133) (7 732163) (8 732193) (9 732222) (10 732252) (11 732281))
298 (2006 (12 732311) (1 732340) (2 732370) (3 732399) (4 732429) (5 732458)
299 (6 732488) (7 732517) (7.5 732547) (8 732576) (9 732606) (10 732636)
300 (11 732665))
301 (2007 (12 732695) (1 732725) (2 732754) (3 732783) (4 732813) (5 732842)
302 (6 732871) (7 732901) (8 732930) (9 732960) (10 732990) (11 733020))
303 (2008 (12 733049) (1 733079) (2 733109) (3 733138) (4 733167) (5 733197)
304 (6 733226) (7 733255) (8 733285) (9 733314) (10 733344) (11 733374))
305 (2009 (12 733403) (1 733433) (2 733463) (3 733493) (4 733522) (5 733551)
306 (5.5 733581) (6 733610) (7 733639) (8 733669) (9 733698) (10 733728)
307 (11 733757))
308 (2010 (12 733787) (1 733817) (2 733847) (3 733876) (4 733906) (5 733935)
309 (6 733965) (7 733994) (8 734023) (9 734053) (10 734082) (11 734112))
310 (2011 (12 734141) (1 734171) (2 734201) (3 734230) (4 734260) (5 734290)
311 (6 734319) (7 734349) (8 734378) (9 734407) (10 734437) (11 734466))
312 (2012 (12 734496) (1 734525) (2 734555) (3 734584) (4 734614) (4.5 734644)
313 (5 734673) (6 734703) (7 734732) (8 734762) (9 734791) (10 734821)
314 (11 734850))
315 (2013 (12 734880) (1 734909) (2 734939) (3 734968) (4 734998) (5 735027)
316 (6 735057) (7 735087) (8 735116) (9 735146) (10 735175) (11 735205))
317 (2014 (12 735234) (1 735264) (2 735293) (3 735323) (4 735352) (5 735382)
318 (6 735411) (7 735441) (8 735470) (9 735500) (9.5 735530) (10 735559)
319 (11 735589))
320 (2015 (12 735618) (1 735648) (2 735677) (3 735707) (4 735736) (5 735765)
321 (6 735795) (7 735824) (8 735854) (9 735884) (10 735914) (11 735943))
322 (2016 (12 735973) (1 736002) (2 736032) (3 736061) (4 736091) (5 736120)
323 (6 736149) (7 736179) (8 736208) (9 736238) (10 736268) (11 736297))
324 (2017 (12 736327) (1 736357) (2 736386) (3 736416) (4 736445) (5 736475)
325 (6 736504) (6.5 736533) (7 736563) (8 736592) (9 736622) (10 736651)
326 (11 736681))
327 (2018 (12 736711) (1 736741) (2 736770) (3 736800) (4 736829) (5 736859)
328 (6 736888) (7 736917) (8 736947) (9 736976) (10 737006) (11 737035))
329 (2019 (12 737065) (1 737095) (2 737125) (3 737154) (4 737184) (5 737213)
330 (6 737243) (7 737272) (8 737301) (9 737331) (10 737360) (11 737389))
331 (2020 (12 737419) (1 737449) (2 737478) (3 737508) (4 737538) (4.5 737568)
332 (5 737597) (6 737627) (7 737656) (8 737685) (9 737715) (10 737744)
333 (11 737774)))
334 "Alist of Chinese year structures as determined by `chinese-year'.
335 The default can be nil, but some values are precomputed for efficiency.")
337 (defun chinese-year (y)
338 "The structure of the Chinese year for Gregorian year Y.
339 The result is a list of pairs (i d), where month i begins on absolute date d,
340 of the Chinese months from the Chinese month following the solstice in
341 Gregorian year Y-1 to the Chinese month of the solstice of Gregorian year Y.
342 The list is cached in `chinese-year-cache' for further use."
343 (let ((list (cdr (assoc y chinese-year-cache))))
344 (or list
345 (setq list (compute-chinese-year y)
346 chinese-year-cache (append chinese-year-cache
347 (list (cons y list)))))
348 list))
350 ;; Maintainer use.
351 (defun chinese-year-cache-init (year)
352 "Insert an initialization value for `chinese-year-cache' after point.
353 Computes values for 10 years either side of YEAR."
354 (setq year (- year 10))
355 (let (chinese-year-cache end)
356 (save-excursion
357 (insert "'(")
358 (dotimes (n 21)
359 (princ (cons year (compute-chinese-year year)) (current-buffer))
360 (insert (if (= n 20) ")" "\n"))
361 (setq year (1+ year)))
362 (setq end (point)))
363 (save-excursion
364 ;; fill-column -/+ 5.
365 (while (and (< (point) end)
366 (re-search-forward "^.\\{65,75\\})" end t))
367 (delete-char 1)
368 (insert "\n")))
369 (indent-region (point) end)))
371 (defun calendar-absolute-from-chinese (date)
372 "The number of days elapsed between the Gregorian date 12/31/1 BC and DATE.
373 DATE is a Chinese date (cycle year month day). The Gregorian date
374 Sunday, December 31, 1 BC is imaginary."
375 (let* ((cycle (car date))
376 (year (cadr date))
377 (month (nth 2 date))
378 (day (nth 3 date))
379 (g-year (+ (* (1- cycle) 60) ; years in prior cycles
380 (1- year) ; prior years this cycle
381 -2636))) ; years before absolute date 0
382 (+ (1- day) ; prior days this month
383 (cadr ; absolute date of start of this month
384 (assoc month (append (memq (assoc 1 (chinese-year g-year))
385 (chinese-year g-year))
386 (chinese-year (1+ g-year))))))))
388 (defun calendar-chinese-from-absolute (date)
389 "Compute Chinese date (cycle year month day) corresponding to absolute DATE.
390 The absolute date is the number of days elapsed since the (imaginary)
391 Gregorian date Sunday, December 31, 1 BC."
392 (let* ((g-year (extract-calendar-year
393 (calendar-gregorian-from-absolute date)))
394 (c-year (+ g-year 2695))
395 (list (append (chinese-year (1- g-year))
396 (chinese-year g-year)
397 (chinese-year (1+ g-year)))))
398 (while (<= (cadr (cadr list)) date)
399 ;; The first month on the list is in Chinese year c-year.
400 ;; Date is on or after start of second month on list...
401 (if (= 1 (caar (cdr list)))
402 ;; Second month on list is a new Chinese year...
403 (setq c-year (1+ c-year)))
404 ;; ...so first month on list is of no interest.
405 (setq list (cdr list)))
406 (list (/ (1- c-year) 60)
407 ;; Remainder of c-year/60 with 60 instead of 0.
408 (1+ (mod (1- c-year) 60))
409 (caar list)
410 (1+ (- date (cadr (car list)))))))
412 ;; Bound in generate-calendar.
413 (defvar displayed-month)
414 (defvar displayed-year)
416 ;;;###holiday-autoload
417 (defun holiday-chinese-new-year ()
418 "Date of Chinese New Year."
419 (let ((m displayed-month)
420 (y displayed-year))
421 (increment-calendar-month m y 1)
422 (if (< m 5)
423 (let ((chinese-new-year
424 (calendar-gregorian-from-absolute
425 (cadr (assoc 1 (chinese-year y))))))
426 (if (calendar-date-is-visible-p chinese-new-year)
427 (list
428 (list chinese-new-year
429 (format "Chinese New Year (%s)"
430 (calendar-chinese-sexagesimal-name (+ y 57))))))))))
432 ;;;###cal-autoload
433 (defun calendar-chinese-date-string (&optional date)
434 "String of Chinese date of Gregorian DATE.
435 Defaults to today's date if DATE is not given."
436 (let* ((a-date (calendar-absolute-from-gregorian
437 (or date (calendar-current-date))))
438 (c-date (calendar-chinese-from-absolute a-date))
439 (cycle (car c-date))
440 (year (cadr c-date))
441 (month (nth 2 c-date))
442 (day (nth 3 c-date))
443 (this-month (calendar-absolute-from-chinese
444 (list cycle year month 1)))
445 (next-month (calendar-absolute-from-chinese
446 (list (if (= year 60) (1+ cycle) cycle)
447 (if (= (floor month) 12) (1+ year) year)
448 ;; Remainder of (1+(floor month))/12, with
449 ;; 12 instead of 0.
450 (1+ (mod (floor month) 12))
451 1)))
452 (m-cycle (% (+ (* year 5) (floor month)) 60)))
453 (format "Cycle %s, year %s (%s), %smonth %s%s, day %s (%s)"
454 cycle
455 year (calendar-chinese-sexagesimal-name year)
456 (if (not (integerp month))
457 "second "
458 (if (< 30 (- next-month this-month))
459 "first "
460 ""))
461 (floor month)
462 (if (integerp month)
463 (format " (%s)" (calendar-chinese-sexagesimal-name
464 (+ (* 12 year) month 50)))
466 day (calendar-chinese-sexagesimal-name (+ a-date 15)))))
468 ;;;###cal-autoload
469 (defun calendar-print-chinese-date ()
470 "Show the Chinese date equivalents of date."
471 (interactive)
472 (message "Computing Chinese date...")
473 (message "Chinese date: %s"
474 (calendar-chinese-date-string (calendar-cursor-to-date t))))
476 (defun make-chinese-month-assoc-list (l)
477 "Make list of months L into an assoc list."
478 (and l (car l)
479 (if (and (cdr l) (cadr l))
480 (if (= (car l) (floor (cadr l)))
481 (append
482 (list (cons (format "%s (first)" (car l)) (car l))
483 (cons (format "%s (second)" (car l)) (cadr l)))
484 (make-chinese-month-assoc-list (cddr l)))
485 (append
486 (list (cons (int-to-string (car l)) (car l)))
487 (make-chinese-month-assoc-list (cdr l))))
488 (list (cons (int-to-string (car l)) (car l))))))
490 (defun chinese-months (c y)
491 "A list of the months in cycle C, year Y of the Chinese calendar."
492 (memq 1 (append
493 (mapcar (lambda (x)
494 (car x))
495 (chinese-year (extract-calendar-year
496 (calendar-gregorian-from-absolute
497 (calendar-absolute-from-chinese
498 (list c y 1 1))))))
499 (mapcar (lambda (x)
500 (if (> (car x) 11) (car x)))
501 (chinese-year (extract-calendar-year
502 (calendar-gregorian-from-absolute
503 (calendar-absolute-from-chinese
504 (list (if (= y 60) (1+ c) c)
505 (if (= y 60) 1 y)
506 1 1)))))))))
508 ;;;###cal-autoload
509 (defun calendar-goto-chinese-date (date &optional noecho)
510 "Move cursor to Chinese date DATE.
511 Echo Chinese date unless NOECHO is non-nil."
512 (interactive
513 (let* ((c (calendar-chinese-from-absolute
514 (calendar-absolute-from-gregorian (calendar-current-date))))
515 (cycle (calendar-read
516 "Chinese calendar cycle number (>44): "
517 (lambda (x) (> x 44))
518 (int-to-string (car c))))
519 (year (calendar-read
520 "Year in Chinese cycle (1..60): "
521 (lambda (x) (and (<= 1 x) (<= x 60)))
522 (int-to-string (cadr c))))
523 (month-list (make-chinese-month-assoc-list
524 (chinese-months cycle year)))
525 (month (cdr (assoc
526 (completing-read "Chinese calendar month: "
527 month-list nil t)
528 month-list)))
529 (last (if (= month
530 (nth 2
531 (calendar-chinese-from-absolute
532 (+ 29
533 (calendar-absolute-from-chinese
534 (list cycle year month 1))))))
536 29))
537 (day (calendar-read
538 (format "Chinese calendar day (1-%d): " last)
539 (lambda (x) (and (<= 1 x) (<= x last))))))
540 (list (list cycle year month day))))
541 (calendar-goto-date (calendar-gregorian-from-absolute
542 (calendar-absolute-from-chinese date)))
543 (or noecho (calendar-print-chinese-date)))
545 (defvar date)
547 ;; To be called from list-sexp-diary-entries, where DATE is bound.
548 ;;;###diary-autoload
549 (defun diary-chinese-date ()
550 "Chinese calendar equivalent of date diary entry."
551 (format "Chinese date: %s" (calendar-chinese-date-string date)))
553 (provide 'cal-china)
555 ;; arch-tag: 7e5b7e0d-676c-47e3-8696-93e7ea0ab644
556 ;;; cal-china.el ends here