XMM-Newton Science Analysis System: Users' Guide

2.6 Running a SAS task from the command line

For a better understanding of the SAS using command lines, the SAS user can read the taskmain package description. Each sas task can be called by typing its name on the commandline, e.g:

evselect -h

Tasks may be configured by a set of parameters, which are entered on the UNIX command line. Every task has a Parameter Specification File which defines the name and type of each parameter and possibly a default value or allowable range. Parameters may also be entered using the Graphical User Interface (GUI). This reads the parameter specification file and provides a dialog window into which the user can enter parameters. The GUI then launches the task by generating a command line which can then be read in the sas_log file. The task parameter handling system (see: http://xmm.esac.esa.int/sas/current/doc/param/index.html ) is capable of understanding complex expressions for allowable values, in addition to setting default values. Furthermore, parameters can have child-parameters, depending on its value, and this makes possible the implicit setting of controlling parameters, if a child parameter is activated on the command line.

Example:

evselect -xcolumn=RAWX implies -withimageset=yes (unless -withimageset=NO explicitly set)

This represents large advantages at the time of writing scripts, which can be much more compact than in the past. However, "old" scripts have to be revised to avoid setting implicitly undesired parameters.

Each SAS task supports the following command line options:

• -h provides information about the command line options.
• -d launches the GUI for this specific task
• -p prints all parameters with their default and current value.
• -t turns on tracing information from the libraries.
• -m displays the HTML documentation of the task using Netscape.
• -c no clobber prevents files to be overwritten.
• -v prints the version number of the task.
• -V (code) level set the verbosity level of the task. The value ranges from 0 to 10 and the larger the verbosity value, the more messages will be produced. Default value is 1, a value of 4 is recommended for a good verbose control. Larger values are only recommended for debugging purposes.
• -w (code) suppresses warning messages. If no value is given all warnings are suppressed. Multiple options can be given, e.g.: -w 10 -w NoAttitudeData -w LowDisk will suppress all warnings with code NoAttitudeData and LowDisk and shows only the first 10 of all other warnings.
• -param=value set the value of parameter param to value

If the task uses the ODF Access Layer (OAL), the command line option -odf ${odf}$ or -o ${odf}$ is recognized as well. It specifies the Observation Data File (ODF) that is to be accessed by the OAL. The variable odf can be the name of an ODF summary file as created by the task odfingest or merely the name of a directory containing one. In the latter case the summary file is assumed to have a name ending in *SUM.SAS.

If the task uses the Calibration Access Layer (CAL), the following command line options are recognized:

• -ccf cifname or -i cifname:

  cifname is the name of a data set comprising a table with the name CALINDEX. This will normally be a Calibration Index File (CIF) created by the task cifbuild . cifname can also be the name of a directory. In this case the CALINDEX table is sought in a data set with the default name ccf.cif in the specified directory.

• -ccffiles f1 ... or -f f1 ...

  Blanks, commas, or colons separated list of CCF constituents replace the corresponding ones in the CCF pointed at via the -ccf command line option or the environment variable SAS_CCF (see below). Each specified file must be a valid CCF constituent according to the CCF ICD.

• -ccfpath dir1[:dir2 ... or -a dir1[:dir2 ... ]

  A list of directories separated by commas, that define a search path along which CCF constituents are to be sought. If a CCF replacement file is passed via -ccffiles with its full absolute path any specified search path is not considered in trying to access this constituent.