% @(#)overpldesc.hlq	17.1.1.1 (ESO-IPG) 01/25/02 17:43:47 
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%.COPYRIGHT  (c)  1990 European Southern Observatory
%.IDENT      overpldesc.hlq
%.AUTHOR     RHW, IPG/ESO
%.KEYWORDS   MIDAS, help files, OVERPLOT/DESCRIPTOR
%.PURPOSE    On-line help file for the command: OVERPLOT/DESCRIPTOR
%.VERSION    1.0  9-JUN-1987: RHW Creation
%.VERSION    1.1 14-Mar-1991: RHW Changes acc. to Verification Form
%----------------------------------------------------------------
\se
SECTION./DESC
\es\co
OVERPLOT/DESCRIPTOR                                           9-JUN-1987 RHW
\oc\su
OVERPLOT/DESCRIPTOR frame [descr] [start,end] [offset]
	overplot the contents of a descriptor
\us\pu
Purpose:    
            overplot the contents of a descriptor
\up\sub
Subject:    
            Graphics, frames, descriptors
\bus\sy
Syntax:     
            OVERPLOT/DESCRIPTOR frame [descr] [start,end] [offset]
\ys\pa
            frame     = name of data frame
\ap\pa
            descr     = name of the descriptor; default is HISTOGRAM
\ap\pa
            start,end = first and last data point to be overplotted; end can 
                        be smaller than start; defaults are the first and the 
                        last valid data points in the descriptor.
\ap\pa
            offset    = offset value in y direction (world coordinate units); 
                        default 0.0

\ap\no
Note:       
            After the overplot the last (over)plotted data set is the active
            one and subsequent commands will work on these data.
\on\sa
See also:   
            PLOT/DESCRIPTOR, READ/DESCRIPTOR, WRITE/DESCRIPTOR, COPY/DD
            COPY/DK, COPY/KD, SET/GRAPHICS, ASSIGN/GRAPHICS
\as\exs
Examples:
\ex
            OVERPLOT/DESCRIPTOR YOURFRAME histogram
            This will overplot the descriptor histogram associated with the 
            frame `YOURFRAME'. The descriptor must exist. In this case, it
            should have been created previously by the command STATISTICS/IMAGE
            YOURFRAME.
\xe\ex
            OVERPLOT/DESCRIPTOR YOURFRAME histogram ? 10
            Similar as previous example only now the elements 100,150 will
            be plotted with an offset of 10 units.
\xe \sxe