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NCMatrix * NCMatrix -- Product of NCMatrices

Synopsis

Description

This command allows for the product of composable NCMatrices (or ordinary matrices over the base).

i1 : B = threeDimSklyanin(QQ,{1,1,-1},{x,y,z})
--Calling Bergman for NCGB calculation.
Complete!

o1 = B

o1 : NCQuotientRing
i2 : M = ncMatrix {{x, y, z}}

o2 = | x y z |

o2 : NCMatrix
i3 : sigma = ncMap(B,B,{y,z,x})

o3 = NCRingMap B <--- B

o3 : NCRingMap
i4 : N = ncMatrix {{M},{sigma M}, {sigma sigma M}}

o4 = | x y z |
     | y z x |
     | z x y |

o4 : NCMatrix
i5 : N' = ncMatrix {{sigma sigma M}, {sigma M}, {M}}

o5 = | z x y |
     | y z x |
     | x y z |

o5 : NCMatrix
i6 : N*N'

o6 = | 2*y^2       2*x^2       2*y*x+2*x*y |
     | 2*x^2       2*y*x+2*x*y 2*y^2       |
     | 2*y*x+2*x*y 2*y^2       2*x^2       |

o6 : NCMatrix
i7 : N'*N

o7 = | y*z+y^2-x*z+x*y  -y*z+y*x+x*z+x^2 y^2+y*x+x*y+x^2  |
     | -y*z+y*x+x*z+x^2 y^2+y*x+x*y+x^2  y*z+y^2-x*z+x*y  |
     | y^2+y*x+x*y+x^2  y*z+y^2-x*z+x*y  -y*z+y*x+x*z+x^2 |

o7 : NCMatrix

Ways to use this method: