ncMap -- Make a map to or from an NCRing

Synopsis

• Usage:

  f = ncMap(B,A,m)

• Inputs:
  • A, an instance of the type NCRing, or a Ring
  • B, an instance of the type NCRing, or a Ring
  • m, a list, the images of the generators of A.
• Optional inputs:
  • Derivation => a Boolean value, default value false
• Outputs:
  • f, an instance of the type NCRingMap,

Description

i1 : A = skewPolynomialRing(QQ,(-1)_QQ,{w,x,y,z})
--Calling Bergman for NCGB calculation.
Complete!

o1 = A

o1 : NCQuotientRing

i2 : B = QQ{a,b,c}

o2 = B

o2 : NCPolynomialRing

i3 : f = ncMap(B,A,{a^3,b^2,a+b,a-b})

o3 = NCRingMap B <--- A

o3 : NCRingMap

i4 : f(w*x+2*y)

         3 2
o4 = 2b+a b +2a

o4 : B

i5 : g = ncMap(B,B,{a*b,b^2,c*a*c},Derivation=>true)

o5 = NCRingMap B <--- B

o5 : NCRingMap

i6 : g(a*b)==g(a)*b+a*g(b)

o6 = true

i7 : g(promote(1,B))

o7 = 0

o7 : B

i8 : g(c*a+2*b)

                2
o8 = caca+cab+2b

o8 : B

See also

• NCRingMap -- Type of a map to or from a noncommutative ring.