| Re: manipulating structures [message #53360 is a reply to message #53359] |
Sat, 07 April 2007 19:06   |
rkombiyil
Messages: 59
Registered: March 2006
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Member |
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On Apr 7, 11:33 pm, "Kenneth P. Bowman" <k-bow...@removethis.tamu.edu>
wrote:
> In article <MPG.2080e60786ec3c36989...@news.frii.com>,
> David Fanning <n...@dfanning.com> wrote:
>
>> Ken's explanation is absolutely correct, but if it is
>> really just the plotting of the data that is causing
>> you problems, I'd forget about NANs and just use the
>> MAX_VALUE keyword to set a value less than the "missing"
>> value.
>
>> PLOT, data, MAX_VALUE=999999.0 - 1
>
> This is true, but using "special numbers" to indicate missing data
> is rife with the possibility using the missing value as valid
> data with noticing it. I'm a big advocate of using NaNs
> because they ensure that if you use them by mistake, your result
> will be a NaN (which is usually hard to ignore :-) ).
>
> Ken
Thanks much! I don't trust myself in such circumstances and hence I
agree with Dr.B :-) This prompts me to ask another trivial question,
if I may..Since I have lots of missing data, and I do lots of math
operations (array ops, fft etc. etc.), will these (NaN) propagate all
the way through in such situations? Should I be using them in
conjunction with finite statement? Any pointers as to where one oughta
be careful with these NaNs?
Thanks in advance for your time and sharing your experience,
~rk
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