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days_in_month

Calculates the number of days in a month given month and year.

Prototype

	function days_in_month (
		year   : integer,  
		month  : integer   
	)

	return_val [dimsizes(year)] :  integer

Arguments

year

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

month

An integer array of the same size as year representing months of the year. Values must be 1 to 12.

Return value

A integer array of the same size as year where each value represents the number of days in a particular month.

Description

Calculates the number of days in a month given arrays of months and years.

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, monthday, isleapyear

Examples

Example 1 

dim = days_in_month((/1996,1997,1/),(/2,2,1/))  ; dim = (/29,28,31/)
Example 2

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

year  = (/1996,1997,1/)
month = (/   2,   2,1/)

year@calendar = "standard"
dim = days_in_month(year,month)  ; dim = (/29,28,31/)

year@calendar = "noleap"
dim = days_in_month(year,month)  ; dim = (/28,28,31/)

year@calendar = "allleap"
dim = days_in_month(year,month)  ; dim = (/29,29,31/)

year@calendar = "360_day"
dim = days_in_month(year,month)  ; dim = (/30,30,30/)