Emoslib now builds with ecCodes
With version 4.4.5, Emoslib is being built by default with ecCodes instead of GRIB-API for GRIB handling. To build EMOSLIB with GRIB_API, please set -DENABLE_ECCODES=OFF. See November synchronised release news item for more information.
Overview
From the 000400 version, Emoslib will be using CMake for its compilation and installation. This is part of our aim to achieve a set of homogenisation installation procedures for all ECMWF packages. CMake is a cross-platform free software program for managing the build process of software using a compiler-independent method.
As configure, CMake will run some tests on the user's system to find out if required third-party software libraries are available and notes their locations (paths). Based on this information it will produces the Makefiles needed to compile and install Emoslib.
Requirements
| Compilers | |||
|---|---|---|---|
| C | http://gcc.gnu.org/ | ||
| Fortran | http://gcc.gnu.org/fortran/ | ||
| Utilities | |||
make | http://www.gnu.org/software/make/ | ||
| cmake | http://www.cmake.org/ | version 2.8.11 minimum | |
| ECMWF libraries | |||
ecCodes alternative: grib-api
|
GRIB-API Home (Requires > 1.14) |
for GRIB 1 & 2 support | |
| Third-party libraries | |||
| FFTW | http://www.fftw.org | If you install from Debian / RPM binary packages, please ensure to install development packages! Please also note that shared libraries are used to link by default. This means they need to be accessible at runtime. If you prefer to use static libraries you need to specific -DFFTW_USE_STATIC_LIBS=ON with your Emoslib cmake call. If you build your own FFTW, please make sure also to build the single precision version of FFTW! This means you need to build twice and you need to add --enable-single to your configure call with FFTW. | |
Compilation environment
At ECMWF, SLES11 & OpenSuSE 11.3/13.1 Linux systems (64bit) were used for testing.
Generating the Makefiles with CMake
Please note
If you plan to use Emoslib for higher level tools (Magics, Metview, ...) please consider to use the -fPIC option for linking. Also if you use the gfortran compiler please read our blog entry on the quadmath option.
After changing into the build Emoslib directory, the user has to run CMake with his own options. The command gives feedback on what requirements are fulfilled and what software is still required. Table 1 gives an overview of the different options of configure. The default (without any options) will compile a share library only and install it in /usr/local/.
| CMAKE_INSTALL_PREFIX | where you want to install your Emoslib library | /usr/local |
| CMAKE_BUILD_TYPE | to select the type of compilation:
| RelWithDebInfo |
| ENABLE_ECCODES | choose ecCodes instead of GRIB_API for GRIB decoding | ON |
ECCODES_PATH GRIB_API_PATH | where to find ecCodes/grib-api ( if non-standard installation ) | |
| ENABLE_FFTW | Option to link FFTW, REQUIRED for Octahedral Gaussian grid | ON |
| ENABLE_SINGLE_PRECISION | enable single precision version of library (Caution for BUFR handling and interpolation!) | OFF |
| ENABLE_FORTRAN90 | enable tools which need Fortran 90 (only required for FC=pgf77) | ON |
| ENABLE_INSTALL_TABLES | enable the installations of BUFR/GRIBex tables and LSM | ON |
| LIBEMOS_INSTALL_LIB_DIR | setting directly the name for the library folder in specified prefix; For systems which require a directory with the name "lib64" instead of "lib" set this variable to "lib64" | |
cmake options | doc | default |
|---|
The C and Fortran compilers are chosen by CMake. (This can be overwritten by setting the variables CC and FC, on the command line before you call cmake, to the preferred compiler). Further the variables CMAKE_C_FLAGS or CMAKE_Fortran_FLAGS can be used to set compiler flags for optimisation or debugging.
Compiling the code
After the CMake command has run successfully, the user can compile the library by typing make in the build directory.
Testing your build
After compilation you can test the build library by typing make test.
Installing the library
Once the build and tests have been successfully completed, the command make install copies the library into the correct location on the system. Administrator permission might be required, depending on the installation directory.
Quick installation guide
This is a list of commands needed to install Emoslib. It is assumed “>” is the shell prompt. The Emoslib version number may vary.
>tar -xzf libemos-4.0.0-Source.tar.gz
> cd libemos-4.0.0-Source
> mkdir build ; cd build
> cmake .. -DCMAKE_INSTALL_PREFIX=/path/to/where/you/install/myEmoslib
...
> make
> make test
> make install