method

civil_to_jd

v1_8_7_330 - Show latest stable - Class: Date

civil_to_jd(y, m, d, sg=GREGORIAN)

public

Convert a Civil Date to a Julian Day Number. y, m, and d are the year, month, and day of the month. sg specifies the Day of Calendar Reform.

Returns the corresponding Julian Day Number.

# File lib/date.rb, line 396
  def self.civil_to_jd(y, m, d, sg=GREGORIAN)
    if m <= 2
      y -= 1
      m += 12
    end
    a = (y / 100.0).floor
    b = 2 - a + (a / 4.0).floor
    jd = (365.25 * (y + 4716)).floor +
      (30.6001 * (m + 1)).floor +
      d + b - 1524
    if julian?(jd, sg)
      jd -= b
    end
    jd
  end

civil_to_jd

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