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
-------------------------------
  CurrentRing();
Q[x,y,z]
-------------------------------
  Use Q[a,b];
  RingEnv();
CurrentRingEnv
-------------------------------

Syntax

RingEnv():STRING
RingEnv(E:POLY, IDEAL, MODULE, RATFUN, VECTOR):STRING

CurrentRing

Ring

RingEnvs

RingEnvSet

   <type>ring</type>