BEGPLOT - Open a plotting device

Description:

Set up a device for subsequent PONGO plotting commands. This application allows plotting onto an AGI picture created by a different package (e.g. KAPPA), or the creation of a new base picture.

If a picture created by a run of a previous application is made (using either the "current" picture or selecting using a known picture label see parameter ACTION) then it is possible to overlay new graphics (such as annotations, lines etc.) using the same coordinate system (see the OVERLAY parameter).

This command is an ICL hidden procedure which uses the undocumented PONGO application BEGPONGO.

Usage:

begplot [device] [action] [clear] [overlay]
$\left\{ {\begin{tabular}{l} label=? \\ \end{tabular} } \right.$
action

Parameters:

ACTION = _CHAR (Read and Write)

If 'B', the plotting device will be cleared and the whole of its plotting surface used. If equal to 'C', the current picture will be used and a PGPLOT viewport created inside it. If 'L' then a previously labelled picture (set using KAPPA:PICLABEL) can be selected. Once set, this parameter will retain its value in subsequent invocations of BEGPLOT. ['C']

CHEIGHT = _REAL (Write)

The character height scaling factor. A value of 1.0 implies a nominal character height of 1/40th the viewport height. The value is set by the application from the height of the chosen picture (unless the picture is the base one). The result is written to the global parameter PONGO_CHEIGHT.

CLEAR = _LOGICAL (Read)

If TRUE then the current picture will be cleared of any existing graphics. [TRUE]

DEVICE = DEVICE (Read and Write)

The name of the device to be used for plotting. The names of the currently available devices can be found using the INQUIRE DEVICES=YES command.

The value of the global parameter GRAPHICS_DEVICE is used unless a value is specified on the command line. If GRAPHICS_DEVICE is not defined and no value is specified on the command line, the value will be prompted for.

LABEL = _CHAR (Read)

If ACTION=L is selected then the name of the AGI picture to be selected is given by this parameter. AGI pictures can be labelled using the KAPPA application PICLABEL. ['']

OVERLAY = _LOGICAL (Read)

If TRUE, the PGPLOT viewport created will exactly overlay the the last DATA picture. This is useful for drawing axis labels using BOXFRAME on an image or contour map etc. that has been displayed by another package (e.g. KAPPA:DISPLAY). [FALSE]

XMIN = _REAL (Write)

The left hand edge of the world coordinate limits from the selected picture. This defaults to 0.0 for a new (i.e. not overlaid) picture. The result is written to the global parameter PONGO_XMIN.

XMAX = _REAL (Write)

The right hand edge of the world coordinate limits from the selected picture. This defaults to 1.0 for a new (i.e. not overlaid) picture. The result is written to the global parameter PONGO_XMAX.

YMIN = _REAL (Write)

The lower edge of the world coordinate limits from the selected picture. This defaults to 0.0 for a new (i.e. not overlaid) picture. The result is written to the global parameter PONGO_YMIN.

YMAX = _REAL (Write)

The lower edge of the world coordinate limits from the selected picture. This defaults to 1.0 for a new (i.e. not overlaid) picture. The result is written to the global parameter PONGO_YMAX.