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Re: FIND the indexes of a value in a matrix [message #29982 is a reply to message #29980]

Tue, 02 April 2002 08:34

David Fanning
Messages: 11724
Registered: August 2001

Senior Member

chi-kuei (twcollie@hotmail.com) writes:

> I have a 1000 X 4 matrix. I want to know the position of one value, say,
> 2342, in that matrix. I am able to do this in MATLAB with "find". How can I
> do this in IDL? Is there a command in IDL does this? (I don't see any in the
> help file.) The only thing that I can do is creating for-loops.

In IDL, you use the WHERE function:

index = WHERE(matrix EQ 2342, count)
IF count GT 0 THEN print, index, matrix[index]

--
David W. Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438, E-mail: david@dfanning.com
Coyote's Guide to IDL Programming: http://www.dfanning.com/
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		Re: FIND the indexes of a value in a matrix By: chi-kuei on Tue, 02 April 2002 13:34
		Re: FIND the indexes of a value in a matrix By: David Fanning on Tue, 02 April 2002 08:34

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