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From: Michael Galloy <mgal...@gmail.com>
Newsgroups: comp.lang.idl-pvwave
Subject: Re: negative indices, am I missing something here?
Date: Fri, 02 Nov 2012 16:26:57 -0600
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On 11/2/12 3:53 PM, David Fanning wrote:
> fawltylangu...@gmail.com writes:
>
>> Array subscripts are always clipped. From IDL help:
>>
>> "If an element of the subscript array is less than or equal to zero, the first element of the subscripted array is selected. ...
>>
>> Note: Because of the confusion between the clipping of array subscripts and the use of negative indices (see the next section), it is best to avoid using code that relies on this clipping behavior."
>
> You can think of it as karmic justice for sins of the past. ;-)
>
> Cheers,
>
> David
>
>

Might be a good idea to use

   compile_opt strictarrsubs

to catch these cases.

Mike
-- 
Michael Galloy
www.michaelgalloy.com
Modern IDL: A Guide to IDL Programming (http://modernidl.idldev.com)
Research Mathematician
Tech-X Corporation