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Re: comparing numbers using WHERE doesn't work [message #25343 is a reply to message #25243]

Wed, 06 June 2001 04:47

R.Bauer
Messages: 1424
Registered: November 1998

Senior Member

"Miklos Z. Kiss" wrote:
>
> Hi folks:
> I have noticed a strange occurence when I try to compare a number with
> all the elements of an array. I'll show my situation in an example.
> Consider the following array:
> a = [2.0000, 2.1000, 2.2000, 2.3000, 2.4000, 2.5000, 2.6000].
> Let, x = 2.2000, y = 2.4000
> So, I want to find which elements of a match up with x and y.
> Naturally, I do the following:
>
> index0 = WHERE(a EQ x)
> index0 = index[0] ; convert from 1-D array to single integer.
index0 is now redefined by index[0].

> index1 = WHERE(a EQ y)
> index1 = index[0]
index1 is now redefined by index[0].

But where is index redefined normally index0 and
index1 should have the same value.

I believe you missed something in your example.

>
> So, when I execute, I may get the following:
> PRINT, index0
> 2
>
> PRINT, index1
> -1
>

Reimar

--
Reimar Bauer

Institut fuer Stratosphaerische Chemie (ICG-1)
Forschungszentrum Juelich
email: R.Bauer@fz-juelich.de
http://www.fz-juelich.de/icg/icg1/
=============================================
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http://www.fz-juelich.de/zb/text/publikation/juel3786.html

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[Message index]

		comparing numbers using WHERE doesn't work By: Miklos Z. Kiss on Sat, 02 June 2001 12:15
		Re: comparing numbers using WHERE doesn't work By: R.Bauer on Wed, 06 June 2001 04:47
		Re: comparing numbers using WHERE doesn't work By: Martin Schultz on Tue, 05 June 2001 06:18
		Re: comparing numbers using WHERE doesn't work By: John-David T. Smith on Mon, 04 June 2001 14:24

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