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DRAW

        [GREG1\]DRAW Argument Xc Yc [/CLIP] [/BOX N] [/CHARACTER  N]  [/USER
    [code]]

    This is a powerful command which allows you to make drawings without da-
    ta either by specifying coordinates (Xc,Yc) and  action  desired  (Argu-
    ment), or by interactive use of a cursor.

    The cursor is obtained if Xc and Yc are omitted, and the appropriate ac-
    tion is then specified by keys typed at the keyboard: R is for RELOCATE,
    L  for LINE, M for MARKER, A for ARROW, T for TEXT. In addition, C works
    like T, but prompts for the centering parameter in addition to the text.
    D can be used to DELETE the last operation, and has no action on the op-
    erations which were plotted previously  to  the  current  DRAW  command.
    (Presently  D  has  no  visible action. Use ZOOM REFRESH after.) E exits
    from the cursor routine. ^C will exit AND generate an error,  which  can
    be trapped (useful to regain control inside of forever SIC loops calling
    the interactive cursor repeatedly).

    Other keys gives you the cursor coordinates (in the current angular unit
    when a projection is defined), except that keys '0' '1' '2' and '3' tem-
    porarily (i.e., as long one does not exit from cursor mode)  change  the
    current angular unit in which the cursor coordinates are returned.

    For X11 displays, you may use the mouse buttons for the commands R (left
    mouse button), L (middle mouse button), and E (right mouse button).

    The complete command is written to the LOG_FILE so that you  can  replay
    it  easily.  The option allows you to supersede the default value of the
    coordinate system defined by SET COORDINATE or to  keep  clipping.   The
    code suboption in the /USER option, if present, can be any of 'SECONDS',
    'MINUTES', 'DEGREES', 'RADIANS' (in which case the Xc and Yc coordinates
    are  taken to be in the corresponding unit) or 'ABSOLUTE' (in which case
    Xc and Yc are taken as absolute coordinates, usually exprimed  in  sexa-
    gesimal  format).  The presence of the code suboption is valid only if a
    PROJECTION and a SYSTEM (EQUATORIAL or GALACTIC) are both defined.

    When using the explicit form, Xc and Yc may be equal to  *  to  use  the
    current pen position.

    Any  "realistic"  combination  of  literal values, 0-d and 1-dimensional
    variables is accepted for that command. For example,
    DRAW MARKER A B /USER MINUTES
    will plot markers at each location given by the two arrays A and B (pro-
    vided  they  are  of the same size). A and B must be CHARACTER arrays in
    the case where the "/USER ABSOLUTE" option is used.


Subsections

Gildas manager 2011-04-01