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Re: transforming an array where some values can't [message #10897 is a reply to message #10896]

Sun, 08 February 1998 00:00

alpha
Messages: 49
Registered: September 1996

Member

offenbrg@fondue.gsfc.nasa.gov (Joel D. Offenberg) writes:
> bowler@eisner.decus.org writes:

>> 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)?

> I think what you want is this:

> function xform, input
> temp = alog(input > 1e-7)
> return, temp
> end

> The ">" operator in this case sets a floor on the values of "input"...any
> value less than 1e-7 is replaced with 1e-7.

RSI told us, that the alo10 error was corrected in release 5.1!

so wait

Panther

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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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