invert-transform
transform
&optional
into
=>
inverse
Arguments
transform
A transform.
into
A transform or
nil
.
Values
inverse
A transform.
Description
This function constructs the inverse of
transform
. If
T
is
transform
and
T'
is its inverse, then
TT
' = I. If
into
is non-
nil
it is modified to contain
T'
and returned, otherwise a new transform is constructed and returned.
