### WORLD

Set the world coordinates for the plot

#### Description:

Set up the world coordinate limits for the plot. The world coordinate system is the one in which the data are plotted. It is possible to specify the limits explicitly, or to have them calculated from the range of the data that have been read, or to recall the limits from a previous plot using AGI (SUN/48).

#### Usage:

world action
$\left\{\right\$
[xmin] [xmax] [ymin] [ymax] piclab=?

action

#### Parameters:

##### ACTION = _CHAR (Read and Write)
The way in which the world coordinate limits are to be determined:
• "DATA" – The limits are calculated from the data limits, with a small border added.

• "DATA0" – The limits are calculated as for DATA, but the origin is included as one of the data points.

• "GIVEN" – The limits specified on the command line are used.

• "RECALL" – The coordinates are recalled from a previous plot using the AGI database.

[The value is prompted for.]

##### XMIN = _REAL (Read and Write)
The world coordinate of the left-hand edge of the plot.

The application will determine the value if ACTION is one of "DATA", "DATA0" or "RECALL". If ACTION="GIVEN" and no value is specified on the command line, the value of the global parameter PONGO_XMIN is used.

##### XMAX = _REAL (Read and Write)
The world coordinate of the right-hand edge of the plot.

The application will determine the value if ACTION is one of "DATA", "DATA0" or "RECALL". If ACTION="GIVEN" and no value is specified on the command line, the value of the global parameter PONGO_XMAX is used.

##### YMIN = _REAL (Read and Write)
The world coordinate of the lower edge of the plot.

The application will determine the value if ACTION is one of "DATA", "DATA0" or "RECALL". If ACTION="GIVEN" and no value is specified on the command line, the value of the global parameter PONGO_YMIN is used.

##### YMAX = _REAL (Read and Write)
The world coordinate of the upper edge of the plot.

The application will determine the value if ACTION is one of "DATA", "DATA0" or "RECALL". If ACTION="GIVEN" and no value is specified on the command line, the value of the global parameter PONGO_YMAX is used.

##### PICLAB = _CHAR (Read and Write)
The AGI label of the picture to be recalled.

[If ACTION="RECALL", the value is prompted for.]

##### PROJECTION = _CHAR (Read and Write)
The geometry to be used for plotting the data. This is explained in more detail in the section on projections. Allowed values: "NONE", "TAN", "SIN", "ARC", "GLS", "AITOFF", "MERCATOR" and "STG".

[The value of the global parameter PONGO_PROJECTN is used. If PONGO_PROJECTN is not defined, the default value "NONE" is used.]

##### RACENTRE = _CHAR (Read and Write)
The centre of the projection in RA (i.e. the angle must be specified as hh:mm:ss.sss). This parameter is only required for PROJECTION values other than "NONE".

[The value of the global parameter PONGO_RACENTRE is used. If PONGO_RACENTRE is not defined, the default value "0" is used.]

##### DECCENTRE = _CHAR (Read and Write)
The centre of the projection in declination (i.e. the angle must be specified as dd:mm:ss.sss). This parameter is only required for PROJECTION values other than "NONE".

[The value of the global parameter PONGO_DECCENTRE is used. If PONGO_DECCENTRE is not defined, the default value "0" is used.]

##### ERSCALE = _REAL (Read)
The scale factor to be applied to the EXCOL and EYCOL data when determining the limits of the world co-ordinates. ERSCALE is used only when ACTION = "DATA" or "DATA0". [The value of the global parameter PONGO_ERSCALE is used. If PONGO_ERSCALE is not defined, the default value 1.0 is used.]