The AIPS Software Package

and How To Access It



Topics Covered:

  • What is AIPS?
  • What machine should I use?
  • What is my Userid Number?
  • How do I start AIPS?
  • Where are my AIPS windows?
  • How do I exit AIPS cleanly?


  • What is AIPS?
  • Back To The Top

    The Astronomical Image Processing System (AIPS) software package was developed at NRAO in the late 1970s. Its primary purpose is to calibrate and display radio astronomical data from the VLA, VLBA, or VLBI network. Users unfamiliar with AIPS should read the first three chapters of the AIPS Cookbook and either Chapter 4 (VLA) or Chapter 9 (VLBA/VLBI).

  • What machine should I use?
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    There are 11 public machines available for AIPS:

    RGLINUX9-13 and RTDC2-7.
    More information available here.

    AIPS disks are not cross mounted. If your AIPS files are on RGLINUX9, for example, you must run AIPS on RGLINUX9. Tapes can be read (or written to) remotely by setting remhost in the AIPS verb MOUNT.

  • What is my Userid Number?
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    If you have processed with AIPS at NRAO and were assigned a userid number there, use the same userid number here. If not, please speak to Shoshana K. Rosenthal and she will assign you a number.

  • How do I start AIPS?
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    Steps for getting into AIPS (on, say, RGLINUX9):
    1. setenv DISPLAY RGLINUX9:0.0 (to get AIPS TV when start AIPS)
    2. setenv AIPS_MSG_EMULATOR xterm (to get separate message window, if desired)
    3. aips tst(new, old) tv=local[:n] (to actually start up AIPS)


    AIPS Versions
    AIPS Version Date
    TST 31DEC13
    NEW 31DEC12
    OLD 31DEC08

    General Notes:
    1. All AIPS versions employ time destroy, so back up your data in a timely fashion.

    2. Use AIPS TST, unless you have a good reason not to.

    3. Please start AIPS by typing, for example:

      aips tst tv=local

      The "tv=local" string tells the computer to choose the first available unix socket to start up a TV window. If the computer has lost track of how many TVs are running or has failed to delete temporary lock files, you will have to set this yourself with ":n". Try, for example, "F", "N", or "X".

      Please note that typing, for example:

      aips tst rglinux9:

      will lead to problems for other AIPS sessions. A different set of commands is executed upon startup, which allow only one TV to be opened per machine.

      So, in summary, use "local" and not the machine name.

    4. The MNJ (midnight job) runs on all computers and updates versions NEW and TST.

    5. Running multiple AIPS sessions on the same machine does not speed up processing, since you will just be sharing cpu resources among your own sessions. More importantly, however, it has the potential to lead to unexpected and incorrect results, since parameter and input settings will also be shared.

    Notes about Older AIPS Versions:
    1. NRAO reports: "31DEC07 contains a significant difference from 31DEC06. The pseudo-array processor memory is obtained dynamically rather than being pre-compiled into each "AP" task. This means that each task asks for the memory needed and so should use less disk for large problems and less memory for small problems. This is a large enough change that we chose not to put it into a soon to be frozen version 31DEC06. It has been tested pretty thoroughly although some attributes have yet to be understood entirely."

    2. Very old disk files (created using a pre-April 1998 version of AIPS) can not be read by any of the AIPS versions currently installed on the R&G computers. Trying to read these files may permanently corrupt them and render them useless. Files that were processed with a pre-April 1998 version, then written to tape, are not affected.

  • Where are my AIPS windows?
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    Two icons (windows) will pop up somewhere on your computer screen when you start AIPS:
    1. A TV window (look for picture of ape). This window is necessary for interactive editing and is very useful for the display of data or images at various stages of calibration . To use your TV window, set docrt=1 or dotv=1 in the appropriate AIPS tasks.

    2. A TEKSRV window, which is necessary for running tasks such as TKPL.


  • How do I exit AIPS cleanly?
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    Please exit AIPS by typing "kleenex" instead of "exit." The former exits and gets rid of windows and temporary lock files.