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BaseRing    --    the base ring of a ring


Syntax 
BaseRing(RmodI: (Quotient)RING): RING
BaseRing(K: (Fraction Field)RING): RING

Description
This function gives the "base ring" of a given ring; e.g. if K was constructed as the fraction field of R then BaseRing(K) produces R, if K was constructed as a quotient R/I then BaseRing(K) produces R (see also DefiningIdeal ).

All rings in CoCoA are derived from ZZ via various steps; BaseRing gives the ring which is one step closer to ZZ.

Example 
/**/  Fpx ::= ZZ/(7)[x];
/**/  Fp := BaseRing(Fpx); --> ZZ/(7)
/**/  BaseRing(Fp) = ZZ;
true

See Also