eccodes/tools/grib_set.dox

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/*! \page grib_set grib_set
\section DESCRIPTION
Sets key/value pairs in the input grib file and writes
each message to the output_grib_file.
It fails when an error occurs (e.g. key not found).
\section USAGE
grib_set
[options] grib_file grib_file ... output_grib_file
\section OPTIONS
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-s key[:{s/d/i}]=value,key[:{s/d/i}]=value,... \n
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Key/values to set.
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For each key a string (key:s), a double (key:d) or an integer (key:i)
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type can be defined. By default the native type is set.
\n \n -r \n Repack data. Sometimes after setting some keys involving properties
of the packing algorithm a repacking of data is needed.
This repacking is performed setting this -r option.
\n \n -d value \n
Set all the data values to "value".
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\n \n -p key[:{s/d/i}],key[:{s/d/i}],... \n
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Declaration of keys to print.
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For each key a string (key:s), a double (key:d) or an integer (key:i)
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type can be requested. Default type is string.
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\n \n -P key[:{s/d/i}],key[:{s/d/i}],... \n
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As -p adding the declared keys to the default list.
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\n \n -w key[:{s/d/i}]{=/!=}value,key[:{s/d/i}]=value,... \n
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Where clause.
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Set is only executed for GRIB messages matching all the key/value constraints.
If a GRIB message does not match the constraints it is copied unchanged
to the output_grib_file. This behaviour can be changed by setting the -S option.
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A valid constraint is of type key=value or key!=value.
For each key a string (key:s), a double (key:d) or an integer (key:i)
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type can be defined. Default type is string.
\n \n -7 \n Does not fail when the message has wrong length
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\n \n -S \n Strict. Only GRIB messages matching all the constraints are copied to
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the output file
\n \n -V \n Version.
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\n \n -M \n Multi-field support off. Turn off support for multiple fields in single GRIB message.
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\n \n -g \n Copy GTS header.
\n \n -G \n GRIBEX compatibility mode.
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\n \n -T T | B | M | A \n Message type. T->GTS, B->BUFR, M->METAR (Experimental),A->Any (Experimental).
The input file is interpreted according to the message type.
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\n \n -f \n Force. Force the execution not to fail on error.
\n \n -v \n Verbose.
\n \n
\section grib_set_examples grib_set examples
-# To set productDefinitionTemplateNumber=2 only for the fields with productDefinitionTemplateNumber=11 \n
\verbatim
>grib_set -s productDefinitionTemplateNumber=2 -w productDefinitionTemplateNumber=11 ../data/tigge_pf_ecmwf.grib2 out.grib2
\endverbatim\n
-# To set productDefinitionTemplateNumber=2 only for the fields for which productDefinitionTemplateNumber is not equal to 11 \n
\verbatim
>grib_set -s productDefinitionTemplateNumber=2 -w productDefinitionTemplateNumber!=11 tigge_pf_ecmwf.grib2 out.grib2
\endverbatim\n
-# When a key is not used all the bits of its value should be set to 1 to indicate that it is missing. Since the length
(number of octet) is different from a key to another, the value that we have to code for missing keys is not unique.
To give an easy way to set a key to missing a string "missing" or "MISSING" is accepted by grib_set as follows:\n
\verbatim
>grib_set -s scaleFactorOfFirstFixedSurface=missing,scaledValueOfFirstFixedSurface=MISSING ../data/regular_latlon_surface.grib2 out.grib2
\endverbatim\n
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Since some values cannot be set to missing you can get an error for those keys.\n
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-# To set scaleFactorOfSecondFixedSurface to missing only for the fields for which scaleFactorOfSecondFixedSurface is not missing: \n
\verbatim
>grib_set -s scaleFactorOfSecondFixedSurface=missing -w scaleFactorOfSecondFixedSurface!=missing tigge_pf_ecmwf.grib2 out.grib2
\endverbatim\n
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-# It's possible to produce a GRIB edition 2 file from a GRIB edition 1 just changing the edition number with grib_set.
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At this stage of development all the geography parameters, level and time information is correctly translated, for the product
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definition extra 'set' calls must be done. To do this properly, use the tool grib_filter.\n
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\verbatim
grib_set -s edition=2 ../data/reduced_gaussian_pressure_level.grib1
\endverbatim\n
-# With grib edition 2 is possible to compress data using the jpeg algorithm.
To change packing algorithm from grid_simple (simple packing) to grid_jpeg (jpeg2000 packing):\n
\verbatim
>grib_set -s packingType=grid_jpeg ../data/regular_gaussian_model_level.grib2 out.grib2
\endverbatim\n
-# It's possible to ask grib_api to calculate the number of bits per value needed to pack a given
field with a fixed number of decimal digits of precision. For example if we want to pack a temperature
expressed in Kelvin with 1 digits of precision after the decimal point we can set changeDecimalPrecision=1 \n
\verbatim
>grib_set -s changeDecimalPrecision=1 ../data/regular_latlon_surface.grib2 ../data/out.grib2
rm -f ../data/out.grib2 | true
./grib_set -s changeDecimalPrecision=1 ../data/regular_latlon_surface.grib2 ../data/out.grib2
\endverbatim\n
*/