CoCoA:Use

Use

command for making a ring active

Description

This command makes a ring active, i.e. makes a ring the current ring.

The command

Use N ::= E; where E is a ring, is a shorthand for N ::= E; Use N;

If you want to change the ring inside a function you should

call <ttref>Using</ttref> instead.

Example

  Use S ::= Q[x,y,z];
  RingEnv();
S
-------------------------------
  T ::= Z/(3)[a,b];
  Use T;
  RingEnv();
T
-------------------------------
  Use Q[u];  -- note that <quotes>Use</quotes> can be used w/out a ring identifier
  RingEnv();
CurrentRingEnv
-------------------------------
  CurrentRing();
Q[u]
-------------------------------

Syntax

Use N

where N is either the identifier of an existing ring or a ring
itself.

Accessing Other Rings

Using

   <type>ring</type>