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Re: divide by zero problems [message #15358 is a reply to message #15355]

Tue, 11 May 1999 00:00

davidf
Messages: 2866
Registered: September 1996

Senior Member

Mark Rehbein (mrehbein@aims.gov.au) writes:

> I'm having problems with floating point divide by zero's. The
> application I'm using IDL for is image composition and masking.
> Now to composite or average the images I do the following:
>
> composite=sum image/ sum mask.
>
> sometimes my images are very cloudy and as such my "sum mask" has zero's
> in it and likewise for my "sum image". So I get divide by zero's and
> NaN's in my resultant composite image. In fact I get whole image of
> NaN's in my composite even though my sum image and sum mask have decent
> values in them.

Usually, something like this works:

composite = sum_image / (sum_mask > 10E-6)

Cheers,

David

--
David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: davidf@dfanning.com
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[Message index]

		Re: divide by zero problems By: edward.s.meinel on Thu, 13 May 1999 00:00
		Re: divide by zero problems By: <asowter on Thu, 13 May 1999 00:00
		Re: divide by zero problems By: korpela on Tue, 11 May 1999 00:00
		Re: divide by zero problems By: davidf on Tue, 11 May 1999 00:00

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