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Re: transforming an array where some values can't [message #10907 is a reply to message #10901]

Thu, 05 February 1998 00:00

S Penzes
Messages: 4
Registered: February 1998

Junior Member

How about

function xform, input
temp = alog(input)
temp(where(finite(temp) EQ 0))=1e-7
return, temp
end

Works for me.

bowler@eisner.decus.org wrote:

> I'm trying to write a function that will transform an arbitrary array by taking
> hte natural log of every element in the array.
>
> What I have is
>
> function xform, input
> temp = alog(input) ; I realize I could combine these 2 statements
> return, temp ; but it makes debugging easier
> end
>
> Unfortunately, I can't guarentee that there won't be some elements that are
> zero and thus invalid arguments to alog. what's the "most efficient" way to
> take the alog of any element that's greater than 0 and set the value of ony
> that are less than or equal to 0 to some small value (1e-7 for example)?
>
> TIA,
> Bruce

--
Steven Penzes (Steven.nospamPenzes@dres.dnd.ca)
Note: remove "nospam" from Reply-To and .signature

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[Message index]

		Re: transforming an array where some values can't By: Evilio del Rio on Mon, 09 February 1998 00:00
		Re: transforming an array where some values can't By: alpha on Sun, 08 February 1998 00:00
		Re: transforming an array where some values can't By: offenbrg on Fri, 06 February 1998 00:00
		Re: transforming an array where some values can't By: S Penzes on Thu, 05 February 1998 00:00
		Re: transforming an array where some values can't By: meron on Thu, 05 February 1998 00:00

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