CoCoA:RingEnvSet

From ApCoCoAWiki

RingEnvSet

set of names of the ring environments

Description

This function returns the list of the identifiers of the rings on

which the object E is dependent. Similar to <ttref>RingEnv</ttref>,

this function also works on lists and matrices and returns the set of ring environments of all entries. ...needless to say that it may be quite slow on big inputs!

Example

  Use R ::= Q[x,y,z];
  L1 := [x, y];
  L2 := [x, y, 0, 5/4];
  Use S ::= Z/(3)[a,b];
  RingEnvSet(L1);
[<coc_quotes>R</coc_quotes>]
-------------------------------
  RingEnvSet(L2);
[<coc_quotes>R</coc_quotes>, <coc_quotes/>]
-------------------------------
  RingEnvSet([L2, a+b]);
[<coc_quotes>R</coc_quotes>, <coc_quotes/>, <coc_quotes>S</coc_quotes>]
-------------------------------

Syntax

RingEnvSet(E:LIST, MAT, POLY, IDEAL, MODULE, RATFUN, VECTOR):LIST of STRING

CurrentRing

Ring

RingEnv

RingEnvs

   <type>ring</type>