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Re: Grib data

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  • Subject: Re: Grib data
  • Date: Mon, 15 Aug 2005 10:01:00 -0600 (MDT)
On Mon, 15 Aug 2005, Nelson Brandon K A1C AFWA/SCSA wrote:

> Robb,
>
>
>
>             I got the data from several parameters and compared it to the
> same data I got from the same gribfile using wgrib.  Several of your
> floating point calculations are off.  A few of the datapoints are off by 1-2
> 10 millionths... I know this is a negligible amount but I thought you might
> be able to fix and also thought you would want to know.
>

what file are you referring too? us057g1010t04a000000000  what parameter
are you referring too, values? it would be good to have a reference so i
can check this out. i use floats for the calculations, that may be
descepancy of values. most instruments, calculations  are only accurate to
hundreds or thousands, that's why floats was used.

previous question about speeding up indexing, it probably as fast as
it's going to get because only reading necessary info, skipping over data
parts.

robb...

>
>
> v/r
>
> Brandon
>
>

===============================================================================
Robb Kambic                                Unidata Program Center
Software Engineer III                      Univ. Corp for Atmospheric Research
address@hidden             WWW: http://www.unidata.ucar.edu/
===============================================================================