ISAP Version 2.1- Problems, Bugs, and Fixes

  • For some Solaris and Linux window managers - the cross hairs and the "selection box" invoked with the left button are not appearing in the plot window although they are active. This is being investigated

  • The "Send Mail" button does not work under Linux - no mail is sent.

  • PHT-S files from pipeline 10 will not read in - this is fixed in ISAP v2.2 - a beta test version is available.

  • For LWS data, when running the procedure "Selection Info" in the "tool kit" (invoked by circling data with the right button) - the routine will fail with the message:

  • % XMANAGER: Caught unexpected error from client application. Message follows...
    % Attempt to call undefined procedure/function: 'SPLIT_AAL_STAT'.
    LIA must be downloaded  as well. The solution is to download LIA v8.0 and the 8.1 patch as part of your ISAP environment. See instructions here.
  • There is a bug that prevents PHT-S files from being read-in. To fix it, in the routine pro/ral/ line 415 should be changed to: info_def = {type:aar.type, header:hdr, $

  • If you read-in and write-out too many files from ISAP  (say, more than 28 in total)  you may encounter an error message ( indicating that ISAP has reserved too many logical unit numbers) like this:

  • "FATAL: Unable to open FITS file" The solution is to go to the window in which you started-up ISAP and type the command:
    ISAP> close,/all
    This will free up the unit numbers and allow ISAP to reuse them.
  • Currently, if you use the Special Function "Merge Group of AARs" to merge the positions (stored data sets) of a raster map - then you must merge _all_ raster map positions (the full number in the original map). If you merge together an incomplete number of raster positions, ISAP will produce a composite data set, and will be able to write such a data set, but will be unable to read this file back into ISAP, because the number of positions claimed present in the file's primary header will not match the number of positions in the file.

  • If  you are using LINUX and you spectrum fails to be shown on the display window, or if  you are using a 24-bit display monitor, and your color table is corrupted such that the colors in ISAP flash, add the following two lines to your .Xdefaults file in your home directory:

  • idl.gr_depth: 8
    idl.gr_visual: PseudoColor

    (and restart your x-session)

    Additionally, various other color table problems have been reported under LINUX: The normal blue borders of the ISAP windows come up white on some installations. Also, when circling data while holding down the left or right mouse buttons, the "select box," (normally white on black) may not appear (black on black).

    To fix this we have added the command:


    For a 24 bit monitor you may have to add one additional line so the script begins:

    device, true_color=24

    to the start_isap.idl script, but this does not always solve these problems. Complete solutions to these problems are not yet known, but the problems listed should not significantly interfere with data reduction.

  • If you use the VMS version of ISAP, the line fit module will not work properly in some cases, due an IDL

  • bug in the VMS implementation of modal widgets. To solve this problem, we recommend running ISAP within the IDL developmental environment. You may do this by editing the "" startup script and changing the last line:$ SPAWN IDL isap_temp:start_isap.idl
    $ SPAWN IDL/DE isap_temp:start_isap.idl
    This will fix the problems with modal widgets and the line fit module will operate correctly.
  • Sometimes ISAP windows will overfill your screen. Before starting ISAP you may resize ISAP's windows in one of two ways.
  • If you are using the Common Desktop Environment (CDE) windowing system, it is highly recommended that you set the window font size to a size less than or equal to 3 before entering ISAP (you may immediately reset it to a larger value after starting isap so that any other applications will come up with the font size you prefer). Using a font size of 4 or higher will cause these known problems:
  • Some pop-ups such as Header Editor, and "acknowledge" (for transmitting messages) may come up blank
  • Some button labels will be truncated
  • "Show Linelist" in the Line Fit Module will develop a problem, where the list may be prematurely truncated. The last wavelength should be 205.17. To see the original line list point your web browser to
  • If starting isap the first time fails, and you get a message like this:

  • "% Unable to open validation file: /usr/local/pkg/rsi/idl/idl.genver.
    No such file or directory"

    This means that you are not using the genver licensing system.
    In this case you should comment out (with a '#') the line:

    setenv LM_LICENSE_FILE $IDL_DIR/bin/license.dat

    in the file "isap" and also type the unix command:

    unsetenv LM_LICENSE_FILE $IDL_DIR/bin/license.dat
    to clear things.

  • Sometimes the 2nd or 3rd order baseline fits fails in `Line Fit.'  This happens when a narrow data range exists: x_max - x_min << x_mean, and likewise for the y-axis. It is due to IDL's matrix inversion routine being not very robust.  To avoid the problem, try removing  a constant baseline first or x-shifting the data to close to 0.

  • There is a mix-up in the MSX filters presented in the Photometry module. The filter labeled "msx_D.dat" is actually the MSX E-band data, and the D-band data is missing. You can fix this by renaming the msx_D.dat file in /data/filters/ to msx_E.dat and downloading the missing msx_D.dat file here.

  • Sometime, when fitting multiple guassians to a set of lines with line fit, the uncertainty in the line fit parameters and area that are reported are unreasonably large. The cause of the problem is not known. The suggestion is that the user compare  the  integrated area of the line with the 3 times the rms of the data (3-sigma) reported by line fit times the width of the line, to gain an appreciation of the S/N of the line. (This quantity is reported by the fit as well.)

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    Last update: 20 April 2003