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Re: newbie question on array manipulation [message #66287 is a reply to message #66285]

Tue, 05 May 2009 06:06

Jean H.
Messages: 472
Registered: July 2006

Senior Member

ben.bighair wrote:
> On May 5, 7:40 am, jpardila <blu...@gmail.com> wrote:
>> What is the best way to manipulate one array and remap its values
>> according to conditions?
>> Let's say I have a 2-d array, for all the elements equal to 5 I want
>> to change their values to 0. For values equal to 10 I want to convert
>> to 1 and so on. I am really confused and don't know if to use IF,
>> where, for or while. Thanks for answering this basic one.
>> JP
>
> Hi,
>
> The simplest is to use where - don't forget to use the output COUNT
> argument shown here as "na".
>
> a = WHERE(array EQ 10, na)
> if (na GT 0) then array[a] = 1

Also, if you have several values to changes, you can create a new array.
For example, if you want to change 5 -> 0 and 0 -> 10, but you don't
want to change the old 5 to 10!

copy = array ;copy the array
a = WHERE(array EQ 10, na)
if (na GT 0) then copy[a] = 1

Jean

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[Message index]

		Re: newbie question on array manipulation By: jpardila on Tue, 05 May 2009 23:54
		Re: newbie question on array manipulation By: ben.bighair on Tue, 05 May 2009 06:24
		Re: newbie question on array manipulation By: Jean H. on Tue, 05 May 2009 06:06
		Re: newbie question on array manipulation By: ben.bighair on Tue, 05 May 2009 04:53

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