astTranMap

Create a TranMap

Description:

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

A TranMap is a Mapping which combines the forward transformation of a supplied Mapping with the inverse transformation of another supplied Mapping, ignoring the un-used transformation in each Mapping (indeed the un-used transformation need not exist).

When the forward transformation of the TranMap is referred to, the transformation actually used is the forward transformation of the first Mapping supplied when the TranMap was constructed. Likewise, when the inverse transformation of the TranMap is referred to, the transformation actually used is the inverse transformation of the second Mapping supplied when the TranMap was constructed.

Synopsis

AstTranMap astTranMap( AstMapping map1, AstMapping map2, const char options, ... )

Parameters:

map1
Pointer to the first component Mapping, which defines the forward transformation.
map2
Pointer to the second component Mapping, which defines the inverse transformation.
options
Pointer to a null-terminated string containing an optional comma-separated list of attribute assignments to be used for initialising the new TranMap. The syntax used is identical to that for the astSet function and may include " printf" format specifiers identified by " %" symbols in the normal way.
...
If the " options" string contains " %" format specifiers, then an optional list of additional arguments may follow it in order to supply values to be substituted for these specifiers. The rules for supplying these are identical to those for the astSet function (and for the C " printf" function).

Returned Value

astTranMap()
A pointer to the new TranMap.

Notes:

Status Handling

The protected interface to this function includes an extra parameter at the end of the parameter list descirbed above. This parameter is a pointer to the integer inherited status variable: " int status" .