### AST_FRAME

Create a Frame

#### Description:

This function creates a new Frame and optionally initialises its attributes.

A Frame is used to represent a coordinate system. It does this in rather the same way that a frame around a graph describes the coordinate space in which data are plotted. Consequently, a Frame has a Title (string) attribute, which describes the coordinate space, and contains axes which in turn hold information such as Label and Units strings which are used for labelling (e.g.) graphical output. In general, however, the number of axes is not restricted to two.

Functions are available for converting Frame coordinate values into a form suitable for display, and also for calculating distances and offsets between positions within the Frame.

Frames may also contain knowledge of how to transform to and from related coordinate systems.

#### Invocation

RESULT = AST_FRAME( NAXES, OPTIONS, STATUS )

#### Arguments

##### NAXES = INTEGER (Given)
The number of Frame axes (i.e. the number of dimensions of the coordinate space which the Frame describes).
##### OPTIONS = CHARACTER $\ast$ ( $\ast$ ) (Given)
A character string containing an optional comma-separated list of attribute assignments to be used for initialising the new Frame. The syntax used is identical to that for the AST_SET routine. If no initialisation is required, a blank value may be supplied.
##### STATUS = INTEGER (Given and Returned)
The global status.

#### Returned Value

##### AST_FRAME = INTEGER
A pointer to the new Frame.

#### Examples:

FRAME = AST_FRAME( 2, ’ Title=Energy Spectrum’ , STATUS );
Creates a new 2-dimensional Frame and initialises its Title attribute to the string " Energy Spectrum" .
FRAME = AST_FRAME( 2, ’ Label(1)=Energy, Label(2)=Response’ , STATUS );
Creates a new 2-dimensional Frame and initialises its axis Label attributes to suitable string values.

#### Notes:

• A null Object pointer (AST__NULL) will be returned if this function is invoked with STATUS set to an error value, or if it should fail for any reason.