Name
       spjitter - ISAAC (SW and LW) jitter spectroscopic reduction

Synopsis
       spjitter [flags] [options]

Description
       spjitter  reduces  images  taken in jitter spectroscopic mode. It has a
       list of several possible algorithms with associated parameters for each
       reduction stage.

       spjitter  has been developped to reduce jitter spectroscopic data taken
       from ISAAC in both chopping and non-chopping modes with both SW  or  LW
       arms.  Although  some  features   are  specific to this instrument, the
       same algorithms should work on similar data.

       spjitter is configured through an initialization file. The name of this
       file is defaulted to spjitter.ini but can  be  changed  through the use
       of the -f option. In thefollowing documentation, this file is  referred
       to as the ini file.

Process
       The  reduction  process is composed by files classification, correction
       of the distortion, re-centering of the  frames,  flatfield  correction,
       averaging,   wavelength  calibration,  frames  combination,  detection,
       extraction of a spectrum. Describing all the algorithms in this command
       is far beyond the scope of this manual page.

       A  documentation  about  the  spjitter  algorithm is in progress at the
       moment.

       To setup the process, you need first to generate a default spjitter.ini
       file  and then change parameters according to your needs. This initial-
       ization file is self-documented.

Flags
       Flags which can be activated on the command-line are the following:

       -t or --time
              Activate time estimation tools. This actually triggers  a  clock
              when the process is running and produces duration estimations in
              CPU and user time at the end.

Options
       -c or --calib  calib.ascii
              This option can only be used together with  the  -g  option.  It
              will generate a default ini file where the names of the calibra-
              tion files  are  deduced  from  the  contents  of  the  provided
              ’calib.ascii’  file.  This  file should contain two columns: the
              first one gives the name of the calibration file, the second one
              specifies its type.

       -f or --file  filename
              Changes  the name of the ini file from spjitter.ini to filename.

       -g or --generate
              Generates a default ini file in the  current  directory,  and  a
              default  empty  frame list called framelist.ascii.  You can fill
              up the ASCII list of input names by using the ls command:
              ls -1 *.fits >> framelist.ascii
              or:
              dfits *.fits | fitsort DPR.TYPE >> framelist.ascii
              Of  course,   the   list   of   frames   need   not   be   named
              ’framelist.ascii’,  this  is the default name only. Change it if
              you wish in the ini file.

       -A or --algorithm  algo
              is used together with the -g option to generate an ini file with
              the  defaults  set for the specified instrument. Possible values
              for algo are chop, nochop or auto.

       -w or --gui
              Launches a GUI to use spjitter

       -h or --help
              Displays a short reminder of possible options and flags.

       -i or --in  filename
              This option can only be used together with  the  -g  option.  It
              will  generate  a  default  ini file where the name of the input
              framelist is not the  default  but  the  one  provided  to  this
              option.

       -o or --out  basename
              This  option  can  only  be used together with the -g option. It
              will generate a default ini file where the  output  basename  is
              not the default but the one provided to this option.

Files
       The  ini  file  which is generated by using the -g option is self-docu-
       mented, all parameters are described in the file comments.

       The ini file consists of [Sections] followed by
       keyword = value lines.

       Section names and keywords are case-insensitive. Values  associated  to
       keuwords  may be integer, floating point numbers, character strings, or
       flags. Types associated to keywords are usually indicated in  the  com-
       ment  section.  Character strings as keyword values are case-sensitive.
       Flags are given as Yes/Y/yes or No/N/no.

       Comments in the ini file are identified by lines starting with  a  hash
       (#) sign, and generally everything after a semicolon (;) and before the
       end of the line. The semicolon is not mandatory, the two  5A  following
       lines are strictly equivalent:

       ExposureTime = 1000 ; integer value in seconds
       ExposureTime = 1000

       It is advised to use the -A option when the ini file is generated.