The program searchdup searches a catalog file for sources observed multiple times. It produces a file that can be plotted with a standard plotting utility (e.g. smongo), or a new catalog file in the same format of the input one, with just one record per independent source.
It can be used either to "compact" the catalog, leaving only one entry for each independent source (sources not within the same beam of the telescope), or to identify those sources observed more often.
It has been developed in a "quick and dirty" fashion, and is tailored to the format of the data records in the Medicina water maser catalog.