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monoid(...,SkewCommutative=>...) -- specify Skew commuting variables in the ring

Synopsis

Description

The SkewCommutative option specifies which variables will skew-commute when the monoid is used to create a ring. The value true indicates that all of the variables skew-commute. Otherwise, the value of the option may be a list of symbols or indices corresponding to the skew-commuting variables.

i1 : ZZ/101[e_0..e_3,       SkewCommutative => true]

      ZZ
o1 = ---[e ..e ]
     101  0   3

o1 : PolynomialRing, 4 skew commutative variable(s)
i2 : (e_0+e_1+e_2+e_3)^2

o2 = 0

      ZZ
o2 : ---[e ..e ]
     101  0   3
i3 : ZZ/101[x,y,vars(0..4), SkewCommutative => vars(0..4)]

      ZZ
o3 = ---[x..y, a..e]
     101

o3 : PolynomialRing, 5 skew commutative variable(s)
i4 : c*b*a*d

o4 = -a*b*c*d

      ZZ
o4 : ---[x..y, a..e]
     101
i5 : ZZ/101[x,y,vars(0..4), SkewCommutative => {2..6}]

      ZZ
o5 = ---[x..y, a..e]
     101

o5 : PolynomialRing, 5 skew commutative variable(s)
i6 : c*b*a*d

o6 = -a*b*c*d

      ZZ
o6 : ---[x..y, a..e]
     101
i7 : R = ZZ[x,y,z, SkewCommutative => {x,y}]

o7 = R

o7 : PolynomialRing, 2 skew commutative variable(s)
i8 : x*y

o8 = x*y

o8 : R
i9 : y*x

o9 = -x*y

o9 : R
i10 : x*z-z*x

o10 = 0

o10 : R

This option may also be used when creating a new ring from an existing ring, creating a tensor product ring, or symmetric algebra.

Further information

See also

Functions with optional argument named SkewCommutative :