up previous next
IsConstant

checks if a ringelem is in the coefficient ring

Syntax 
IsConstant(X: RINGELEM): BOOL

Description
This function tests whether the value of a RINGELEM of a polynomial ring actually lies in the image of the coefficient ring. It is equivalent to checking that the degree in each indeterminate is 0.

Example 
/**/  QQx ::= QQ[x];
/**/  Use QQx[y,z];
/**/  IsConstant(y+1);
false
/**/  IsConstant(x+1);
true

See Also