DIFMAP: Difmap is a fast, flexible, editing and mapping program. While
        it is primarily intended for single polarization continuum VLBI
        data, it has been used to map VLA and other connected-element
        interferometer dat. It is designed to work on one source at a time
        and takes advantage of this and the large internal memory available
        in the current generation of workstation to minimize the time spent
        reloading data and regenerating models. Difmap also provides the
        user with a wide range of interactive plots available with a single
        command. This frees the user from time-consuming specification of
        input parameters, and encourages a better familiarity with the data.
        (from the Introduction to 'The Difmap Cookbook' by Greg Taylor)

The current version is 2.3a

This is the second major version of Difmap. Instead of reading the Caltech
VLBI merge format, this version reads UV FITS files directly. Support for
UV FITS files is limited to single-source files containing one frequency-id
(one set of possibly differing IF frequencies).
Multiple sub-arrays, IFs, spectral-line channels and polarization are
now supported.

DifMap is available at I.R.A. on DEC-alpha and Linux work-stations.

To start the program enter:  difmap

At the difmap prompt type:   0> help difmap

Difmap will list a set of general help topics, followed by a list of all
difmap command. Type help and the name of any of these commands to get
further help. (Hint: type help observe to get started).

To get out difmap, type:     0> exit

The DIFMAP User's Guide are available in two diffent forms:

      Postscript files at the address:
           http://www.ira.inaf.it/ira-docs/calcolo.html

      Manuals at the room 307

Contact persons:  

           F.Mantovani   fmantovani@ira.inaf.it
           T.Venturi     tventuri@ira.inaf.it
           F.Tinarelli   tinarelli@ira.inaf.it