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 files. 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 `exfits.log' -o FILE Output extraction data to FILE. Default is stdout. -s MINROW,MAXROW Row bounds (integer) for simple extraction (inclusive). -t MINCOL,MAXCOL Extract vertically, with an integer range of columns. -u, --unifspec Output unifspec instead of the default text. -v, --verbose Display info about extraction, default if interactive. -?, --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: