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HOME > Monitoring_and_Data > Oceanic and Atmospheric Data > Reanalysis: Atmospheric Data > wgrib2-grib_out

wgrib2: -grib_out


The -grib_out option writes the decoded grid to a specified file in grib2 format. Normally you would use the -grib option as this option just copies the original grib (sub)message. The -grib_out option has to repack or compress the decoded grid which is much slower. You would only use the -grib_out option when you have modified the decoded grid by the -undefine, -import, -rpn, or some other option that modifies the decoded grid. Use the -set_grib_type option to specify the grib packing and -set_scaling to specify the scaling. When the -set_grib_type option is not used, the packing defaults to simple. When the -set_scaling option is not used, the scaling is retained from the input grib message unless a -rpn or -import option is executed. These two options reset the scaling to the default because they can alter the range of grid point values.


-grib_out file_name


$ wgrib2 new.grb2 -undefine out-box -10:10 20:40 -grib_out small.grb2
1:0:d=2005082812:HGT:1000 mb:78 hour fcst:
The above routine sets all the grid points outside the 10W-10E 20N-40N to undefined and then writes the resultant field as a grib file in small.grb2. This file will be much smaller than the original field.

Hint: by proper use of the -undefine and -grib_out options, one should be able to send horizontal boundary conditions for regional models very very quickly. Imagine just sending 4 lines of horizontal boundary conditions.

Hint: gzip

See also: -text, -netcdf -spread -bin -ieee -import_bin, -import_grib, -import_ieee, import_grib -grib -rpn -set_grib_type -undefine

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Page last modified: July 28, 2016
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