# Revision history [back]

Indeed, in Sage the name of the undeterminates matters. You can define the mapping as follows:

sage: h = bRing.hom([aa])
sage: h
Ring morphism:
From: Number Field in a with defining polynomial b^2 + 1
To:   Number Field in a with defining polynomial a^2 + 1
Defn: a |--> a
sage: h(bb) == aa
True


Indeed, in Sage the name of the undeterminates matters. matters, this is not a bug. Think about the multivariate case to be convinced of the reason why.

You can define the mapping as follows:

sage: h = bRing.hom([aa])
sage: h
Ring morphism:
From: Number Field in a with defining polynomial b^2 + 1
To:   Number Field in a with defining polynomial a^2 + 1
Defn: a |--> a
sage: h(bb) == aa
True


Indeed, in Sage the name of the undeterminates indeterminates matters, this is not a bug. Think about the multivariate case to be convinced of the reason why.

You can define the mapping as follows:

sage: h = bRing.hom([aa])
sage: h
Ring morphism:
From: Number Field in a with defining polynomial b^2 + 1
To:   Number Field in a with defining polynomial a^2 + 1
Defn: a |--> a
sage: h(bb) == aa
True