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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,
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.