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eimsim (eimsim-2.4.2) [xmmsas_20211130_0941-20.0.0]

Input and output directories and many-observation mosaics:

The tasks in the eimsim package need to know the names of the directories in which they can respectively read input files and write output files. All the tasks construct these directory names in the same way: via parameters obsidroots, prdssubdir, simgensubdir and simopsubdir. (There is an additional `directory' parameter pseudoprodsubdir which is intended just to contain non-vignetted exposure maps. If these ever become part of the standard product set, this parameter would become obsolete.) The parameter obsidroots is intended to contain a list of directory stem names (although at time of writing only 1 element is permitted). For each member of this list, the tasks append the string from parameter prdssubdir to the stem to generate the name of the directory in which to look for inputs. These input directories must be present before any eimsim tasks are run. The string from parameter simopsubdir is appended to the stem to generate the name of the directory in which to write observation-specific outputs; whereas simgensubdir gives rise to a single subdirectory off the PWD, which is to contain all the non-observation-specific output files. The eimsim tasks will `mkdir' the appropriate simopsubdir and simgensubdir subdirectories if these are not already present.

As described in the cookbook subsection (4.1), the input files comprise templates taken from the SSC product files for a particular XMM observation. Each `input' directory, derived from successive elements of the obsidroots list, must contain template files which relate to no more than a single XMM observation. Now, in the cookbook section, you will note that I specified that these files should be in a subdirectory named `product' off the present working directory; the reason for this is that the default value of obsidroots is `.' and the default value of prdssubdir is `product'.

To illustrate with an example in which some non-default values are used: The command

        eimsimprep obsidroots='/mydisk/obs1 /mydisk/otherfiles/obs2' \
          prdssubdir=infiles simopsubdir=sim_output simgensubdir=generic \
generates the following subdirectory names:
Must pre-exist, and contain the proper products:

Created by the eimsim tasks:

The task will look for product templates from the first observation in /mydisk/obs1/infiles and in /mydisk/otherfiles/obs2/infiles for those from the second.

XMM-Newton SOC -- 2021-11-30