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yyyymmddhh_time

Creates a one-dimensional array containing year-month-day-hour (yyyymmddhh) values.

Available in version 6.1.0 and later.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"  ; This library is automatically loaded
                                                             ; from NCL V6.2.0 onward.
                                                             ; No need for user to explicitly load.

	function yyyymmddhh_time (
		yrStrt [1] : integer,  
		yrLast [1] : integer,  
		hrStep [1] : integer,  
		TYPE       : string    
	)

Arguments

yrStrt

An integer specifying the initial year. If the attribute "noLeapYear" is associated with yrStrt and it is set to True, then February will only have 28 days.

yrLast

An integer specifying the last year.

hrStep

An integer specifying the hourly increment. This must be a factor of 24. Common hrStep values are 1, 3, 4, 6, 8, 12, 24.

TYPE

A string specifying the numeric type to be returned ["integer", "float", "double"].

Return value

A one-dimensional array containing values of the form yyyymmddhh. The first value will correspond to January 1 of yrStrt. The last value will correspond to December 31 of yrLast. In addition, the attributes "long_name" and "units" will be set, and the return value will have a named dimension "time".

Description

For each year-month-day-hour of each year, the value yyyymmddhh = (yyyy*1000000 + mm*10000 + dd*100 + hh) is returned. The 'mm' values start at 1 [January] and end at 12 [December]. Leap years will have a 29 February.

Examples

The following require that contributed.ncl be loaded prior to invoking the function.

       load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"

Example 1

Create a one-dimensional [1D] array of type integer spanning 1991 through 2012.

      yyyymmddhh = yyyymmddhh_time(1991, 2012, 6, "integer")
      print(yyyymmddhh)

The above returns a 1D array of length 32144 values.

Variable: time
Type: integer
Total Size: 128576 bytes
            32144 values
Number of Dimensions: 1
Dimensions and sizes:   [time | 32144]
Coordinates: 
            time: [1991010100..2012123118]
Number Of Attributes: 2
  long_name :   time
  units :       YYYYMMDDHH
(0)     1991010100
(1)     1991010106
(2)     1991010112
(3)     1991010118
(4)     1991010200
(5)     1991010206
(6)     1991010212
(7)     1991010218
[snip]
(32136) 2012123000
(32137) 2012123006
(32138) 2012123012
(32139) 2012123018
(32140) 2012123100
(32141) 2012123106
(32142) 2012123112
(32143) 2012123118

Example 2

Create a yyyymmddhh variable named "time" that spans April 15 1901 at 3Z thru September 21 2001 15Z. Make the yrStrt and yrLast span the required years. Then use NCL's Coordinate Subscripting to subset the returned 1D array.

      TIME = yyyymmddhh_time(1901, 2001, 3, "integer")
      time = TIME({1901041503:2001092115})    ; coordinate subscripting
      print(time)

The above returns a 1D array of length 293477 values.