# Changes between Version 8 and Version 9 of WRF4G2.0/Preprocessor

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Timestamp:
Jan 15, 2016 12:48:03 PM (7 years ago)
Comment:

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 v8 == preprocessors in WRF4G == As mentioned, the preprocessor is called before the WPS in each chunk. It must be an executable file that can be written in any language, and accepts 5 arguments. These are the initial date, the end date (as YYYY-mm-dd HH:MM:SS), the input data path, member number and initialization month number (4 and 5 arguments are available when extdata_member variable is used). After preprocessing, the preprocessor must copy the properly formatted input data to a folder called WPS/grbdata. As mentioned, the preprocessor is called before the WPS in each chunk. It must be an executable file that can be written in any languages, and accepts at least 3 arguments. These are the initial date, the end date (as YYYY-mm-dd HH:MM:SS) and the input data path. If you want to add more arguments, you have to configure the preprocessor_optargs variable in the [wiki:WRF4G2.0/Experiment experiment.wrf4g] file. After preprocessing, the preprocessor must copy the properly formatted input data to a folder called WPS/grbdata. WRF4G provides some preprocessors as examples. These are located under \$WRF4G_DEPLOYMENT_DIR/repository/apps/preprocessor directory. In order to create preprocessors, they have to be located in the wrf4g_files/bin directory of the specific experiment.