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GRIB-API is entirely included in ecCodes without any change to its Fortran 90, Python , and C interfaces. The only function which has been removed is grib_handle_new_from_template which was already deprecated in GRIB-API and replaced by the grib_handle_new_from_samples.
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The migration from GRIB-API to ecCodes will not affect the user software and will be managed in installation and linking phases. Nevertheless, very significant changes in the library have been performed to implement the encoding of different types of messages and in particular for BUFR.
To be confident that ecCodes behaves as GRIB-API, for what concerns as far as the GRIB decoding and encoding is concerned, we are performing a set of tests. At the moment all the standard tests are passing without problems. One important aspect of the library is performance and we are continuously checking that ecCodes performs at least as well as GRIB-API. In the latest version the difference in performance is not significant. ecCodes is performing as well as GRIB-API and in some tests it is slightly better.
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