Voir la source de Some pointers about standalone installation of the IOIPSL library

This page is mostly for "do-it-yourself" people interested in installing the IOIPSL library.

== Prerequisites ==
IOIPSL is written in Fortran, so you need to have a Fortran compiler at hand (gfortran in the following examples), as well as an available NetCDF library compiled using that same compiler.

One of the IOIPSL install scripts uses ksh (Korn Shell), which is not always available (Bash, Bourne Again Shell, is now the standard). So you might want to first install it, e.g. on Linux-Ubuntu:
<syntaxhighlight lang="bash">
sudo apt install ksh
</syntaxhighlight>
If that is not an option (e.g. you do not have super-user privileges to install ksh) the you will need to manually modify a file (see section "Know problems and issues worth knowing about" below)

=== Downloading the IOIPSL library sources ===
One can do this using svn (subversion):
<syntaxhighlight lang="bash">
svn checkout --username icmc_users --password icmc2022 https://forge.ipsl.jussieu.fr/igcmg/svn/IOIPSL/trunk IOIPSL
</syntaxhighlight>
where the trailing argument ''IOIPSL'' is customizable to whatever (non existing) subdirectory name one wants to have the library put in.
As of April 2022 the IOIPSL distribution requires username/password authentification (not a big issue as a this does not require any specific registration step as the generic username/password given in the svn command line above can be used). 

=== The makeioipsl_fcm compilation script and related FCM architecture files ===
The main script to compile the library is '''makeioipsl_fcm''', located in the distribution's top directory. It uses FCM (Flexible Configuration Management) to know about specific configuration options and set-up and thus requires (just like the GCM) appropriate ''architecture files'' (check out the [[WhatIs:_The_target_architecture_("arch")_files|page about these)]]. These files contain information on which compiler to use, what compilation options to use, where relevant libraries are located etc. In practice one must thus create these ASCII text files in the '''arch/''' subdirectory. The naming convention is rather straightforward, when the script '''makeioipsl_fcm''' is run with the option '''-arch somename''', it will look for files '''arch/arch-somename.env''', '''arch/arch-somename.path''' and '''arch/arch-somename.fcm'''.

You will most likely use the IOIPSL with LMDZ6. In that case it is recommended to use the same set of architecture files to compile IOIPSL and the GCM.

== Building the IOIPSL library ==
Building the IOIPSL library then merely requires running the '''makeioipsl_fcm''' with the adequate mandatory '''-arch''' option (note that one can learn about all the possible options by running '''./makeioipsl_fcm -h'''), e.g.:

<syntaxhighlight lang="bash">
./makeioipsl_fcm -arch gfortran
</syntaxhighlight>


=== Checking that the install was successful ===
If the previous step went well the '''IOIPSL/lib''' directory should contain the library:
<pre>
libioipsl.a
</pre>
The '''IOIPSL/inc''' directory should contain the following module files:
<pre>
calendar.mod   flincom.mod   histcom.mod  restcom.mod
defprec.mod    fliocom.mod   ioipsl.mod   stringop.mod
errioipsl.mod  getincom.mod  mathelp.mod
</pre>
And the '''IOIPSL/bin''' directory should contain the ''rebuild'' utility:
<pre>
flio_rbld  rebuild
</pre>

Congratulations! You can now use the IOIPSL library.


== Know problems and issues worth knowing about ==
* ksh is needed to compile "out of the box"; if ksh is not available then the workaround is to replace line
<syntaxhighlight lang="bash">
#!/bin/ksh
</syntaxhighlight> 
to 
<syntaxhighlight lang="bash">
#!/bin/bash 
</syntaxhighlight>
in the '''IOIPSL/ins_m_prec''' file prior to running the makeioipsl_fcm script.
* Recent versions of the IOIPSL fails to work properly if compiled by gfortran version 4.8.5 (see e.g. https://trac.lmd.jussieu.fr/Planeto/ticket/62 ) but works fine with more recent versions of the compiler (tested with versions 7.2+)


05/08/2022

[[Category:HowTo]]