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

    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 in the current active window if  Xc  and  Yc  are
    omitted,  and  the appropriate action 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  op-
    eration,  and  has no action on the operations which were plotted previ-
    ously to the current DRAW command. 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  re-

    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,
    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.


Gildas manager 2014-07-01