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2.9.7 Accessing Other Rings
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There are a variety of ways of interacting with a ring outside of the
current ring.
If a variable contains an object which does not depend
on a user-defined ring---for example an integer---that object can be
immediately accessed and used within any ring.
Built-in CoCoA functions should be smart enough to take into account
the rings in which their value was defined, for example
GBasis
,
LT
,
wdeg
,...
If you want to move an object from one ring to another, think
mathematically and use a
RINGHOM
and
apply
.
However there are handy (slower) shortcuts like
image [OBSOLESCENT]
and
BringIn
,
or the constructors
matrix
and
RingElem
.
QZP
,
ZPQ
are NOT YET IMPLEMENTED.