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Sets key/value pairs in the input grib file and writeseach writes each message to the output_grib_file. It fails when an error occurs (e.g. key not found).
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Where clause. 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 unchangedto unchanged to the output_grib_file. This behaviour can be changed setting the option -S. For each key a string (key:s) or a double (key:d) or a long (key:l) type can be defined. Default type is string.
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