isPurePower -- determine whether a ring element is a pure power of a variable
Synopsis
Usage:
B=isPurePower f
Inputs:
f, a ring element, an element of a polynomial ring
Outputs:
B, a Boolean value, true if f is a nonzero power of a variable and false otherwise
Description
isPurePower tests a ring element in a polynomial ring to determine whether or not it is nonzero and a power of a variable. isPurePower is used in the lex-plus-powers LPP code.
i1 : R=ZZ/32003[a..c];
i2 : isPurePower a^4
o2 = true
i3 : isPurePower (a*b^5)
o3 = false
i4 : isPurePower (a^3-b^3)
o4 = false
See also
LPP -- return the lex-plus-powers (LPP) ideal corresponding to a given Hilbert function and power sequence
isLPP -- determine whether an ideal is an LPP ideal