[gradsusr] Regrid or constrain grid dimensions after opening grib file?

[Brian Gaze]

Jeff,

Thanks. Perhaps I didn't explain well. That is what I do at the moment, but
if a script generates X number of charts for a region it seems to complete
much more quickly if the grib file has been regridded for that region
rather than constrained using set lat and set lon. Perhaps the overhead is
in opening the bigger file?

Brian



On Fri, 12 Feb 2021 at 17:05, <gradsusr-request at gradsusr.org> wrote:

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>    1. Regrid or constrain grid dimensions after opening grib    file?
>       (Brian Gaze)
>    2. Re: Regrid or constrain grid dimensions after opening     grib
>       file? (Jeff Duda)
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> ----------------------------------------------------------------------
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> Message: 1
> Date: Fri, 12 Feb 2021 16:39:13 +0000
> From: Brian Gaze <brianw.gaze at googlemail.com>
> To: gradsusr at gradsusr.org
> Subject: [gradsusr] Regrid or constrain grid dimensions after opening
>         grib    file?
> Message-ID:
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> FkfOprA at mail.gmail.com>
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>
> Hi,
>
> I know it is relatively straightforward to define a new grid using wgrib2
> but I wondered whether it is possible to do something similar in GRaDS? So
> just storing the new grid temporarily in memory whilst the script is
> working on the file data, for example to generate charts for a smaller
> region than the original grid covers.
>
> Essentially I'm trying to optimize without going through the overhead of
> writing out a new file using wgrib2.
>
> Thanks
>
> Brian
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> Message: 2
> Date: Fri, 12 Feb 2021 09:49:20 -0700
> From: Jeff Duda <jeffduda319 at gmail.com>
> To: GrADS Users Forum <gradsusr at gradsusr.org>
> Subject: Re: [gradsusr] Regrid or constrain grid dimensions after
>         opening grib file?
> Message-ID:
>         <
> CAAig09AFSEWXmiGvuSmBhBq-PmAJWRTpMfMAfxBAg8awL3QOdg at mail.gmail.com>
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>
> Yes. Restrict the dimension environment.
>
> 'set lat [bounds]'
> 'set lon [bounds]'
> 'set t [bounds]'
> 'set z [bounds]'
>
> 'define field'
>
> (perform operations on field)
>
> On Fri, Feb 12, 2021 at 9:47 AM Brian Gaze <brianw.gaze at googlemail.com>
> wrote:
>
> > Hi,
> >
> > I know it is relatively straightforward to define a new grid using wgrib2
> > but I wondered whether it is possible to do something similar in GRaDS?
> So
> > just storing the new grid temporarily in memory whilst the script is
> > working on the file data, for example to generate charts for a smaller
> > region than the original grid covers.
> >
> > Essentially I'm trying to optimize without going through the overhead of
> > writing out a new file using wgrib2.
> >
> > Thanks
> >
> > Brian
> >
> > _______________________________________________
> > gradsusr mailing list
> > gradsusr at gradsusr.org
> > http://gradsusr.org/mailman/listinfo/gradsusr
> >
>
>
> --
> Jeff Duda, Research Scientist
> University of Colorado Boulder
> Cooperative Institute for Research in Environmental Sciences
> NOAA/OAR/ESRL/Global Systems Laboratory
> Boulder, CO
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