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ispan

Creates an array of equally-spaced integer values.

Prototype

	function ispan (
		start  [1] : integer,  
		finish [1] : integer,  
		stride [1] : integer   
	)

	return_val [*] :  integer

Arguments

start

Value at which to start.

finish

Value at which to end. Can be less than start.

stride

A stride value indicating the spacing of the integer values between start and finish.

Description

This function returns an array of integer values beginning at start and ending at finish. Each element will be separated by the value of stride. The stride must be positive, and start and finish can be any valid integers.

If finish is less than start, then the values will be reversed.

See Also

span, fspan

Examples

Example 1

   x = ispan (1,10,1)      ; "x" = (/1,2, ..., 10/) 
                           ; (10 values)
   y = ispan (-100,100,10) ; "y" = (/-100, -90, ..., 0, 10, ... 90, 100/)
                           ; (21 values)

Example 2

To generate a 1D float array, you can use NCL's implicit coercion by multiplying the ispan result by a float value. Or, in V5.2.0 or later, you can use span: 

   mlon = 128
   y = ispan (0,mlon-1,1)*1.  ; y = (/0.,1.,2., ..., 127./) (128 values)
;  y = span (0,mlon-1,1.)     ; y same as above

   dlon = 360./mlon
   lon  = ispan(0,mlon-1,1)*dlon  ; lon = (/0, 2.8125, ... , 357.1875/)
;  lon  = span(0,mlon-1,dlon)   ; lon = (/0, 2.8125, ... , 357.1875/)