exfits is a simple tool to perform extractions on HST STIS 2D FITS spectra. It supports an equal-weighted row extraction, or a mesa weighting function. exfits can also trace a FITS image, providing a reasonable guess for the row corresponding to a star.

exfits can be run as an interactive shell, or entirely from the command line, in batch mode.


Usage: exfits [OPTION...] [FILE]

`exfits' is a program designed to perform extractions on 2D spectra from FITS
exfits has two primary modes: batch and interactive. When run without
arguments, or when using the `-i' switch, exfits will be run interactively.
Otherwise, the program can be run with command-line input only. There are
currently six extraction types:
   `-c'    Mesa-shaped extraction across floating-point rows
   `-s'    Box-shaped extraction across integer rows
   `-t'    Box-shaped vertical extraction with integer rows
   `-e -c' Echelle mode mesa-shaped extraction across floating-point rows
   `-e -s' Echelle mode box-shaped extraction across integer rows
   `-e'    Echelle mode extraction of all rows
2D Echelle spectra can be extracted in either normal or Echelle mode
('-e').  In Echelle mode the row numbers are treated relative to each
order and each order is written to a separate file.
The extraction types including '-c' can take up to three parameters. For a
non-Echelle FITS file, omitting the central row causes the programto perform a
trace which automatically chooses the brightest row in thefile for the center.
exfits records its doings in a log file, which defaults to `exfits.log' in the
current working directory. exfits will also write cspec-compatible text files,
with appropriate headers commented with the `#' character.
  -c PLATW,BASEW[,CENTER]    Extract with careful method, specify mesa plateau,
                             base, and optionally row center. If the center is
                             not specified, a trace will determine the center.
  -e                         Extract data in Echelle mode.  (Fails if the input
                             FITS are not properly formated Echelle data)
  -f, --fits                 Output FITS image.
  -i, --interactive          Enter interactive terminal session.
  -l FILE                    File to write session log to. Default is
  -o FILE                    Output extraction data to FILE. Default is
  -s MINROW,MAXROW           Row bounds (integer) for simple extraction
  -t MINCOL,MAXCOL           Extract vertically, with an integer range of
  -u, --unifspec             Output unifspec instead of the default text.
  -v, --verbose              Display info about extraction, default if
  -?, --help                 Give this help list
      --usage                Give a short usage message
  -V, --version              Print program version


This software requires installation of the NASA FITSIO libraries. Install this first:


This software also requires two custom libraries developed for the Treasury Project:

After downloading, successfully compiling, and installing those libraries you are ready to download and compile exfits:


©2006 The University of Minnesota