Inverse transformation defined?

This attribute
indicates whether a Mapping is able to transform coordinates in the

`"`

inverse`"`

direction (i.e. converting output coordinates back into input coordinates). If this
attribute is non-zero, the inverse transformation is available. Otherwise, it is not. - Type:

All Mappings have this
attribute.

The TranInverse attribute value for a CmpMap is given by
the boolean AND of the value for each component Mapping.

The
TranInverse attribute of a FrameSet applies to the transformation which converts
between the FrameSet

`’`

s current Frame and its base Frame (as specified by the
Current and Base attributes). This value is given by the boolean AND of the
TranInverse values which apply to each of the individual sub-Mappings required
to perform this conversion. The TranInverse attribute value for a FrameSet
may therefore change if a new Base or Current Frame is selected. -
An error will result if a Mapping with a TranInverse value of zero is used to transform coordinates in the inverse direction.

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