matrix_dataset::locate

Source: dataset/matrix/matrix_dataset__locate.pro

 matrix_dataset::locate
        Mark one or more positions on a PHA matrix

 Usage:
        locs = dsref -> locate([/noprint, /one_value])

 Keyword:
        one_value ?     input   If set, then just read a single value
                                and exit.
        noprint ???     input   If set, then don't print out the
                                position etc.
        nomain                  If set, then don't prompt for creating
                                a variable at the $MAIN$ level.

 Restrictions:
        A PHA matrix must be present, and the device
        must support cursor reading.

 History:
        Original (from MARKPOS): 23/11/95; SJT
        Add noprint keyword: 28/11/95; SJT
        Use !mouse.button instead of !err: 24/11/00; SJT
        Fix colours so the cross-hairs show in 24-bpp: 6/2/01; SJT