Chap. 1 : General introduction

post_it has been developped in IDL by Eric Guilyardi. It uses SAXO routines which has been developped by Sébastien Masson. post_it may help visualise and analyse netcdf data outputs from models automaticly without knowing properly the SAXO routines. However I recommend the user to have some notions of IDL to use this software. A good way to do this is also to read the SAXO documentation on ​http://forge.ipsl.jussieu.fr/saxo/

Directories and files

You should create two directories in your home directory :

• 'POST_IT' (where to download the sources through svn)
• 'SAXO' (which can be a link to Sébastien Masson's directory '/usr/home/smasson/SAXO_DIR/SRC/' if you have an account in LOCEAN or once again dowload the sources through svn).

post_it has a new structure since it has been managed by a svn server. The 'POST_IT' directory contains 7 main directories :

chromios.locean-ipsl.upmc.fr:/.autofs/home/mklod/POST_IT> ls
config  doc  grids  out  procs  tools  usr
chromios.locean-ipsl.upmc.fr:/.autofs/home/mklod/POST_IT>

The main files which the user will have to change are :

hromios.locean-ipsl.upmc.fr:/.autofs/home/mklod/POST_IT/usr> ls -l
-rw-r--r--        1 mklod lodyc  2956 Jul 12 17:52 init.pro
lrwxrwxrwx   1 mklod lodyc        8 Jul 11 18:23 i.pro -> init.pro
lrwxrwxrwx   1 mklod lodyc        5 Jul 11 18:26 p -> p.pro
-rw-r--r--         1 mklod lodyc   8198 Jul 17 17:59 plt_def.pro
-rw-r--r--         1 mklod lodyc 63820 Jul 17 19:10 post_it.pro
-rw-r--r--         1 mklod lodyc       45 Jul 11 18:25 p.pro
lrwxrwxrwx   1 mklod lodyc        18 Jul 11 18:23 r.pro -> ../procs/reset.pro
chromios.locean-ipsl.upmc.fr:/.autofs/home/mklod/POST_IT/usr>

Launch IDL and POST_IT

• Parametrize the init.pro file (the path variable where to find the POST_IT and SAXO directories -> mandatory ; other directories such as homedir -> you can leave the default values).
• Launch idl in the 'usr' directory.

chromios.locean-ipsl.upmc.fr:/.autofs/home/mklod/POST_IT/usr> idl
IDL Version 6.2 (linux x86 m32). (c) 2005, Research Systems, Inc.
Installation number: 500138.
Licensed for use by: CNRS/ IPSL
IDL>

• Execute the 'init.pro' file in the IDL window (@init or @i if you made a link : ln -s init.pro i)

  IDL> @i
  % Compiled module: KEEP_COMPATIBILITY.
  % Compiled module: FIND.
  % Compiled module: PATH_SEP.
  ......................
  

• Execute the 'post_it.pro' in the IDL window (@p or p if you made a link : ln -s p.pro p)

  IDL> p
  % Compiled module: P.
  % Compiled module: POST_IT.
  % Compiled module: DEF_WORK.
  % Compiled module: PLT_DEF.
  % Compiled module: DECODE_CMD.
  ........................
  

Chap.2 : File post_it.pro

General description and a first example

post_it.pro is the file in which you will work. It defines the in line commands which will be read by post_it so as to get the plot you want. For instance :

cmdline = [ $
; var             on   exp      grid  plt   timeave  date1   spec  disp   proj   out
  'sohtc300   1     2L24   T       xy   100y      1860     -       1       1        v', $

'lastline 0' ]

This means that you want the sohtc300 variable to be visualised from a netcdf file called '2L24_100y_1860_*_grid_T.nc' on a 2D plot 'xy'.
The result is the following picture.

As a consequence, the names of the netcdf files are standardized and follow this pattern :
'Experiment'_'Frequency'_'Date1'_'Date2'_'Grid Type'.nc

More details about the variables defined in 'post_it.pro'

• Variable 'spec_base_list' defines where to find a specific database of files. It should begins with the name of the experiment (here all files beginning with 'CMAP_')

  spec_base_list = [ $ 
   'CMAP = local:/home2/mkdlod/database/CORREL/', $
  ' ']
  

• Variable 'data_base_list' defines also where to find by default all the databases ('ncdf_db'). Il also allows to define generic databases. For instance, 'MRI_db' defines all files beginning with 'MRI' : it can be 'MRI_', 'MRIoCTL', 'MRIo2X'...

  data_base_list =  [ $
  'ncdf_db = local:/home2/mkdlod/database/', $
  'MRI_db = local:/home2/mkdlod/ERIC-LSCE/database/IPCC/',  $
  ' ']