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isleapyear

Determines if a given year is a leap year.

Prototype

	function isleapyear (
		year  : integer   
	)

	return_val [dimsizes(year)] :  logical

Arguments

year

A multi-dimensional integer array or scalar value representing years. Values must be >= 0.

Return value

A logical array of the same size as year. True = leap, False = no leap.

Description

Determines if a given year is a leap year.

In V6.1.0, this function was upgraded to look for a "calendar" attribute attached to the "year" variable. Valid calendars include:

  • "standard" (the default)
  • "gregorian"
  • "julian"
  • "360_day", "360"
  • "365_day", "365"
  • "366_day", "366"
  • "noleap", "no_leap"
  • "allleap", "all_leap"
  • "none"
Also in V6.1.0, this function was upgraded to recognize missing values.

See Also

day_of_year, day_of_week, days_in_month, monthday

Examples

Example 1 

; Every element of isleap will be false in this case
isleap = isleapyear((/1997,1993,1900,1990/))
Example 2

This example shows how to use the new "calendar" attribute, which was added in NCL version 6.1.0. 

year = (/1900,1903,1996,2000,2007/)

year@calendar = "standard"
isleap = isleapyear(year)  ; False, False, True, True, False

year@calendar = "julian"
isleap = isleapyear(year)  ; True, False, True, True, False

year@calendar = "noleap"
isleap = isleapyear(year)  ; False, False, False, False, False

year@calendar = "all_leap"
isleap = isleapyear(year)  ; True, True, True, True, True

year@calendar = "360"
isleap = isleapyear(year)  ; False, False, False, False, False

year@calendar = "365"
isleap = isleapyear(year)  ; False, False, False, False, False