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lapack & blas libraries - these are usually available on all flavours of Linux/Unix. Some systems, notably HPC installations will have special optimized versions of these libraries. These should be used instead (if a version exists for your choice of compiler) to achieve a better performance. You may need to modify the compile configuration to access these optimized libraries.
If the lapack/blas libraries are not available or you choose not to use them, OpenIFS comes with the necessary lapack code. This is disabled by default. Contact openifs-support@ecmwf.int for details.
grib-api (or ecCodes) - the grib-api library and set of commands for working with and manipulating GRIB files. GRIB is the file format used as input and output for OpenIFS. The grib-api software is available for download from the grib-api software pages. Please use the latest version. Although pre-compiled, binary packages are available, please download the source files and compile it. This is to ensure the same compiler and compiler version is used for the models and grib-api, otherwise errors from mismatching modules are likely. See the grib_api for OpenIFS install page for more details on how to build grib_api for the OpenIFS models.
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