Log(0) is still INF. I suggested a max function but the problem then is
to decide what to choose as a cutoff value.
On Jan 30, 2004, at 4:04 PM, Sylvia Murphy wrote:
> Hi ben,
> you're right, NCL does not have a where function, but it does have
> the algerbraic > and < operators. In your case I think this will work
> if
> you
> don't mind setting all negative values to zero rather than missing:
>
>
> x<0
>
> will take all values in x < 0 and set them to 0.
>
> sm
>
>
>
> On Fri, 30 Jan 2004, Ben Foster wrote:
>
>>
>> Hi ncl-talk:
>>
>> Here's a simple question. I want to plot log10 of my field, e.g.:
>>
>> var = a->$vars(n)$(time2plot,:,:,lons2plot(i))
>> var = log10(var)
>> ...
>> plot var
>>
>> If there are values of var <= 0., I get -INF in those areas of the
>> array after the log10 (no error or warning messages). It then hangs
>> in the plot call.
>>
>> I don't think ncl has a "where" function, and I don't want to loop
>> w/ conditionals, so what is the best way to take log10 of the field
>> and substitute a fill_value where the array is <= 0.? Thanks,
>>
>> --Ben
>>
>>
>> ----------------------------------------------------------------------
>> -
>> Ben Foster High Altitude Observatory (HAO)
>> foster@ucar.edu phone: 303-497-1595 fax: 303-497-1589
>> Nat. Center for Atmos. Res. P.O. Box 3000 Boulder CO 80307 USA
>> ----------------------------------------------------------------------
>> -
>>
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>
> --
>
>
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>
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