SET VIRTUAL

        LAS\SET VIRTUAL ON|OFF
        LAS\SET VIRTUAL CHECK|NOCHECK

    First  command  enables  or  disables  the  buffering of spectra read in
    CLASS. Default is ON.

    A bug in this buffer handling was present from May2006 to  Nov2008.  See
    the news for Dec08 release at http://www.iram.fr/IRAMFR/GILDAS/ for more
    details. Since occurence was small and is difficult to predict, the sec-
    ond  command  enables  or disables an error which is raised when the bug
    would have been encoutered. This is intended to help users to decide  if
    they  should  rerun  or not the processing of their data with the latest
    CLASS releases where the bug is fixed. Default is NOCHECK.