cal_to_jd

(PHP 4 >= 4.1.0, PHP 5, PHP 7, PHP 8)

cal_to_jd从一个支持的历法转变为Julian Day计数。

说明

cal_to_jd ( int $calendar , int $month , int $day , int $year ) : int

cal_to_jd()函数从一个给定的历法日期计算出Julian天数,支持的历法有 CAL_GREGORIANCAL_JULIANCAL_JEWISHCAL_FRENCH

参数

calendar

选定的历法,可以是CAL_GREGORIANCAL_JULIANCAL_JEWISHCAL_FRENCH中的某一个。

month

数字形式的月份,根据选定的calendar历法来确定范围。

day

数字形式的日期,根据选定的calendar历法来确定范围。

year

数字形式的年份,根据选定的calendar历法来确定范围。

返回值

一个Julian天数。

参见

  • cal_from_jd() - 转换Julian Day计数到一个支持的历法。
  • frenchtojd() - 从一个French Republican历法的日期得到Julian Day计数。
  • gregoriantojd() - 转变一个Gregorian历法日期到Julian Day计数
  • jewishtojd() - 转变一个Jewish历法的日期为一个Julian Day计数
  • juliantojd() - 转变一个Julian历法的日期为Julian Day计数
  • unixtojd() - 转变Unix时间戳为Julian Day计数

User Contributed Notes

ashton at ieee dot org 18-Sep-2016 07:48
The earliest supported date in the Julian calendar is January 2, 4713 BC. The corresponding Julian day count is 1. PHP treats -4713 as equal to 4713 BC, and does not allow the year 0; this practice is different than the custom of astronomers, who treat -4712 as equal to 4713 BC.
ashton at ieee dot org 18-Sep-2016 07:46
Julian days begin at noon, while the days of the Gregorian and Julian calendars are usually thought of as beginning at midnight. For the Gregorian and Julian calendars, the function behaves as if the conversion were performed at noon.