Difference between revisions of "FLEXPART Model/FLEXPARTCompilerSettings"

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This is the README file included now with the FLEXPART distribution
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FLEXPART has been compiled on UIO servers so if you do not need to modify the source code, we suggest you use the pre-compiled version. If you have never used FLEXPART, the pre-compiled version is also helpful to become familiar with this new package. Some tutorials/examples are available on UIO servers.
  
 
== Compiling FLEXPART in a 64-bit environment ==
 
== Compiling FLEXPART in a 64-bit environment ==
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<pre>                      module load grib_api</pre>
 
<pre>                      module load grib_api</pre>
<br/><br/>Please note that grib_api will be loaded automatically when loading flexpart.
 
  
  
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Japser library will also be made available.
  
*&nbsp;FLEXPART:
 
  
How to change and add new code
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== How to change and add new code ==

Revision as of 14:03, 15 September 2014

FLEXPART has been compiled on UIO servers so if you do not need to modify the source code, we suggest you use the pre-compiled version. If you have never used FLEXPART, the pre-compiled version is also helpful to become familiar with this new package. Some tutorials/examples are available on UIO servers.

Compiling FLEXPART in a 64-bit environment

This file describes the required compiler flags for compiling FLEXPART  in a 64-bit computing environment for the gfortran compiler (version 4.2 and onward) and absoft compiler (version 10.1).

Using 64-bit environment brings the advantage of using >2GB main memory for FLEXPART data arrays. However, this requires certain adjustments to the compilation settings of FLEXPART and the external libraries GRIB_API and JASPER (the latter as required by GRIB_API).

The main point to be considered for running FLEXPART in a 64-bit environment is the possiblity to allocate data arrays >2GB. This requires to use the compiler flag -mcmodel=medium. Note that this memory model slows down calculations, if data arrays of less than 2GB are allocated, the use of -mcmodel=small is said to provide slightly better performance.

An additional requirement is that the external libraries must be compiled with the flag -fPIC to allow for the libraries to be located at any position in the computer's main memory. Without this flag, a 'relocation truncated to fit' error will result when linking FLEXPART.

If the compilers are not set to generate 64-bit binaries by default, the flag -m64 should be included for FLEXPART and the external libraries.

All of the required settings for FLEXPART are already made in the cmake configuration files (cmake directory) included in the FLEXPART distribution.


Recommended compilation steps using the gfortran or absoft compiler


  •  JPEG compression is used FLEXPART WINDFIELDS and this requires to compile GRIB-API with jpeg support (JASPER   library). On UIO servers GRIB-API and Jasper are already installed.


            To set-up your environment:


                       module load grib_api


Japser library will also be made available.


How to change and add new code