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yyyymmdd_time

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

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 yyyymmdd_time (
		yrStrt [1] : integer,  
		yrLast [1] : integer,  
		TYPE       : string    
	)

Arguments

yrStrt

An integer specifying the initial year.

yrLast

An integer specifying the last year.

TYPE

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

Return value

A one-dimensional array containing values of the form yyyymmdd. 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 of each year, the value yyyymmdd = (yyyy*10000 + mm*100 + dd) is returned. The 'mm' 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 1850 through 2001.

      yyyymmdd = yyyymmdd_time(1850, 2001, "integer")
      print(yyyymmdd)

The above returns a 1D array of length 57708 values.

Variable: yyyymmdd
Type: integer
Total Size: 230832 bytes
            57708 values
Number of Dimensions: 1
Dimensions and sizes:   [time | 57708]
Coordinates:
            time: [18500101..20071231]
Number Of Attributes: 2
  long_name :   time
  units :       YYYYMMDD
(0)     18500101
(1)     18500102
(2)     18500103
[snip]
(787)   18520227
(788)   18520228
(789)   18520229                   < note leap year
(790)   18520301
(791)   18520302
[snip]
(57705) 20071229
(57706) 20071230
(57707) 20071231

Example 2

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

      TIME = yyyymmdd_time(1901, 2001, "integer")
      time = TIME({19010415:20010921})    ; coordinate subscripting
      print(time)

The above returns a 1D array of length 36685 values.