CoCoA:RingEnv
From ApCoCoAWiki
RingEnv
name of the current ring
Description
The first form of this function returns the identifier for the
current ring. The second form returns the identifier of the ring on
which the object E is dependent.
Example
Use R ::= Q[x,y,z];
I := Ideal(x,y); -- an object dependent on R
S ::= Z/(3)[a,b]; -- define S, but do not make S active
RingEnv(); -- the current ring
R
-------------------------------
RingEnvs(); -- your result here could be different
[<quotes>Q</quotes>, <quotes>Qt</quotes>, <quotes>R</quotes>, <quotes>S</quotes>, <quotes>Z</quotes>]
-------------------------------
Ring(S);
Z/(3)[a,b]
-------------------------------
I;
Ideal(x, y)
-------------------------------
Use S; -- S is now the active ring
I; -- I is labeled by its ring. The label appears explicitly when R
-- is not the current ring.
R :: Ideal(x, y)
-------------------------------
RingEnv(I); -- the ring labeling I
R
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CurrentRing();
Q[x,y,z]
-------------------------------
Use Q[a,b];
RingEnv();
CurrentRingEnv
-------------------------------
Syntax
RingEnv():STRING RingEnv(E:POLY, IDEAL, MODULE, RATFUN, VECTOR):STRING
<type>ring</type>
