# substitute(DiffOp,Ring) -- change the ring of a differential operator

## Synopsis

• Function: substitute
• Usage:
substitute(D, R)
sub(D, R)
• Inputs:
• Outputs:

## Description

Attempts to change the underlying ring of the differential operator by calling substitute for each monomial and coefficient of D

 i1 : R = QQ[x,y] o1 = R o1 : PolynomialRing i2 : D = diffOp{1_R => x^2, x^2 => y^2} 2 2 2 o2 = y dx + x o2 : DiffOp i3 : S = QQ[x,y,z] o3 = S o3 : PolynomialRing i4 : DS = sub(D,S) 2 2 2 o4 = y dx + x o4 : DiffOp i5 : ring DS === S o5 = true