[ncl-talk] Question regarding array indexing

[Prashanth Bhalachandran]

Hello all, 
I have a relatively simple question on array indexing. 

Say, I have an array that is cyclic that contains values from 0 to 360 in steps of 5 degrees (dimension [72]). And I am trying to divide into four quadrants starting from a given theta. Say that the index of the given theta is 13 (out of 73), I define my quadrants that are each 90 degrees as follows : 

Array : theta [73]
Quadrant 1 : theta(13:31)
Quadrant 2: theta(31:49)
Quadrant 3: theta(49:67)
Quadrant 4: theta(67:13)

Now, as you’ll notice, having an index of 67:13 doesn’t imply 67:72 and 0:13, it simply implies 13:67 backwards. How do I index the array such that it takes it in a cyclic fashion? For example (what I don’t want is), in a simpler array of just five dimensions : Variable: a
Type: integer
Total Size: 20 bytes
            5 values
Number of Dimensions: 1
Dimensions and sizes:	[5]
Coordinates: 
(0)	1
(1)	2
(2)	3
(3)	4
(4)	5

ncl 3> print(a(4:2)) 


Variable: a (subsection)
Type: integer
Total Size: 12 bytes
            3 values
Number of Dimensions: 1
Dimensions and sizes:	[3]
Coordinates: 
(0)	5
(1)	4
(2)	3

What I would have liked it is for it to display 5 1 2 3. 

Please let me know how this is possible. 

Thank you all, 
Prashanth 


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