The XIOS Library - Revision history

Jmauxion at 09:57, 30 April 2026

2026-04-30T09:57:07Z

Emillour: /* axes, domains and grids */

2026-04-14T16:08:00Z

‎axes, domains and grids

Emillour: /* axes, domains and grids */

2026-04-14T16:06:51Z

‎axes, domains and grids

Martin.turbet at 14:01, 5 February 2026

2026-02-05T14:01:52Z

Emillour at 08:52, 30 January 2026

2026-01-30T08:52:07Z

Aurelien.falco: /* Examples & adding outputs */

2025-03-05T10:58:17Z

‎Examples & adding outputs

Aurelien.falco: /* Examples & adding outputs */

2025-03-05T10:43:34Z

‎Examples & adding outputs

Aurelien.falco: Detail on how to (easily?) add field into field_def_physics.xml

2025-02-25T16:04:09Z

Detail on how to (easily?) add field into field_def_physics.xml

Aurelien.falco: /* Downloading and compiling the XIOS library */ update URL (certificate issue)

2024-11-08T10:20:48Z

‎Downloading and compiling the XIOS library: update URL (certificate issue)

Emillour at 15:55, 27 February 2024

2024-02-27T15:55:21Z

@@ Line 288: / Line 288: @@
 </syntaxhighlight>
 It can also happen that for a given variable we want the interpolation not to be conservative. For example, a variable like the area of a mesh grid should not be interpolated between different domains. Since the interpolation is specific to a domain (and defined in the "domain id"), we have to create a new domain for all the variable that should be interpolated in another way. For the variable "Area" for example, the syntax is as follow :
 * Create the new domain:

@@ Line 132: / Line 132: @@
      <domain_definition>
 ...
-         <domain id="dom_64_49" ni_glo="64" nj_glo="48" type="rectilinear"  >
+         <domain id="dom_64_49" ni_glo="64" nj_glo="49" type="rectilinear"  >
            <generate_rectilinear_domain lat_start="90" lat_end="-90" lon_start="-180" lon_end="174.375" />
            <interpolate_domain order="1"/>

@@ Line 126: / Line 126: @@
      </grid_definition>
 </syntaxhighlight>
 Specifying to output variables on grid '''my_grid_3d''' will trigger XIOS interpolations so that the output fields are on a regular 128x96 longitudexlatitude grid.
 ==== field definitions ====

@@ Line 309: / Line 309: @@
                          <variable id="using_server" type="bool">true</variable>
 </syntaxhighlight>
-* The '''xios_server.exe''' executable should be present alongside the GCM executable '''gcm_***.e''' and they should be run together in MPMD (Multiple Programs, Multiple Data) mode : some of the MPI processes being allocated to the GCM and the others to XIOS ; in practice much less are needed by XIOS than the GCM, this however also depends on the amount of outputs and postprocessing computations, e.g. temporal averaging and grid interpolations, that XIOS will have to do. For example if the MPI execution wrapper is ''mpirun'' and that 26 processes are to be used by the GCM ''gcm_64x52x20_phystd_para.e'' and 2 by XIOS (i.e. using overall 28 processes):
+* The '''xios_server.exe''' executable should be present alongside the GCM executable '''gcm_***.e''' and they should be run together in MPMD (Multiple Programs, Multiple Data) mode : some of the MPI processes being allocated to the GCM and the others to XIOS ; in practice much less are needed by XIOS than the GCM, this however also depends on the amount of outputs and postprocessing computations, e.g. temporal averaging and grid interpolations, that XIOS will have to do. For example if the MPI execution wrapper is ''mpirun'' and that 26 processes are to be used by the GCM ''gcm_64x52x20_phygeneric_para.e'' and 2 by XIOS (i.e. using overall 28 processes):
 <syntaxhighlight lang="bash">
-mpirun -np 26 gcm_64x52x20_phystd_para.e > gcm.out 2>&1 : -np 2 xios_server.exe
+mpirun -np 26 gcm_64x52x20_phygeneric_para.e > gcm.out 2>&1 : -np 2 xios_server.exe
 </syntaxhighlight>

@@ Line 109: / Line 109: @@
      </grid_definition>
 </syntaxhighlight>
-Note that '''grid_3d''' is defined in the XML file and thus may be changed by the user without having to modify the PCM source code.
+Note that '''grid_3d''' is defined in the XML file and thus may be changed by the user without having to modify the PCM source code. For instance by simply adding the following definitions:
+<syntaxhighlight lang="xml">
 ==== field definitions ====
 For XIOS a field is defined with and '''id''' and most be assigned to a reference '''grid''' (this is how XIOS knows a field is a simple scalar, or a surface or a volume, and thus to which computational grid it is related to).e.g.:

← Older revision		Revision as of 10:58, 5 March 2025
Line 283:		Line 283:

	See [[LMDZ XIOS outputs]] for more details on the outputs generated via XIOS for the LMDZ dynamics/physics.		See [[LMDZ XIOS outputs]] for more details on the outputs generated via XIOS for the LMDZ dynamics/physics.
		+
	If you use [[DYNAMICO]], check out the [[Controling outputs in the dynamics with DYNAMICO\|DYNAMICO outputs]] page.		If you use [[DYNAMICO]], check out the [[Controling outputs in the dynamics with DYNAMICO\|DYNAMICO outputs]] page.

@@ Line 282: / Line 282: @@
 === Examples & adding outputs ===
-XML example files for XIOS can be found in '''LMDZ.GENERIC/deftank/xios''' for the [[Overview of the Generic PCM|generic PCM]]. You will find under '''deftank/dynamico''' example files for [[DYNAMICO]] with generic physics.
+See [[LMDZ XIOS outputs]] for more details on the outputs generated via XIOS for the LMDZ dynamics/physics.
+If you use [[DYNAMICO]], check out the [[Controling outputs in the dynamics with DYNAMICO|DYNAMICO outputs]] page.
 == Using the XIOS library in client-server mode ==

@@ Line 12: / Line 12: @@
 The XIOS source code is available for download using svn (subversion). To download it, go to your trunk repository and run the line e.g.:
 <syntaxhighlight lang="bash">
-svn co http://forge.ipsl.jussieu.fr/ioserver/svn/XIOS/trunk XIOS
+svn co http://forge.ipsl.fr/ioserver/svn/XIOS/trunk XIOS
 </syntaxhighlight>
 * To compile the library, one must first have adequate architecture "arch" files at hand, just like for the GCM (see [[The_Target Architecture_("arch")_Files]]). In principle both ''arch.env'' and ''arch.path'' files could be the same as for the GCM; ''arch.fcm'' will of course differ, as XIOS source code is in C++ (along with a Fortran interface). If using a "known" machine (e.g. Occigen, Irene-Rome, Ciclad) then ready-to-use up-to-date arch files for that machine should be present in the ''arch'' directory. If not you will have to create your own (it is advised to use the existing ones as templates!)

@@ Line 175: / Line 175: @@
          </file>
 </syntaxhighlight>
 === Thorougher description with illustrative examples ===