PGPLOT Module: PGBEG -- open a graphics device
INTEGER FUNCTION PGBEG (UNIT, FILE, NXSUB, NYSUB)
INTEGER UNIT
CHARACTER*(*) FILE
INTEGER NXSUB, NYSUB
Note: new programs should use PGOPEN rather than PGBEG. PGOPEN
is retained for compatibility with existing programs. Unlike PGOPEN,
PGBEG closes any graphics devices that are already open, so it
cannot be used to open devices to be used in parallel.
PGBEG opens a graphical device or file and prepares it for
subsequent plotting. A device must be opened with PGBEG or PGOPEN
before any other calls to PGPLOT subroutines for the device.
If any device is already open for PGPLOT output, it is closed before
the new device is opened.
Returns
PGBEG : a status return value. A value of 1 indicates
successful completion, any other value indicates
an error. In the event of error a message is
written on the standard error unit.
To test the return value, call
PGBEG as a function, eg IER=PGBEG(...); note
that PGBEG must be declared INTEGER in the
calling program. Some Fortran compilers allow
you to use CALL PGBEG(...) and discard the
return value, but this is not standard Fortran.
Arguments
UNIT (input) : this argument is ignored by PGBEG (use zero).
FILE (input) : the "device specification" for the plot device.
(For explanation, see description of PGOPEN.)
NXSUB (input) : the number of subdivisions of the view surface in
X (>0 or <0).
NYSUB (input) : the number of subdivisions of the view surface in
Y (>0).
PGPLOT puts NXSUB x NYSUB graphs on each plot
page or screen; when the view surface is sub-
divided in this way, PGPAGE moves to the next
panel, not the next physical page. If
NXSUB > 0, PGPLOT uses the panels in row
order; if <0, PGPLOT uses them in column order.