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addGWu -- the direct sum for two unstable Grothendieck-Witt Classes

Description

This computes the direct sum of the Grothendieck-Witt classes beta and gamma.

i1 : M = matrix(QQ, {{2,1},{1,2}})

o1 = | 2 1 |
     | 1 2 |

              2       2
o1 : Matrix QQ  <-- QQ
i2 : N = matrix(QQ, {{1,2},{2,6}})

o2 = | 1 2 |
     | 2 6 |

              2       2
o2 : Matrix QQ  <-- QQ
i3 : beta = makeGWuClass M

o3 = (| 2 1 |, 3)
      | 1 2 |

o3 : UnstableGrothendieckWittClass
i4 : gamma = makeGWuClass N

o4 = (| 1 2 |, 2)
      | 2 6 |

o4 : UnstableGrothendieckWittClass
i5 : addGWu(beta, gamma)

o5 = (| 2 1 0 0 |, 6)
      | 1 2 0 0 |
      | 0 0 1 2 |
      | 0 0 2 6 |

o5 : UnstableGrothendieckWittClass

Ways to use addGWu:

  • addGWu(UnstableGrothendieckWittClass,UnstableGrothendieckWittClass)

For the programmer

The object addGWu is a method function.


The source of this document is in A1BrouwerDegrees/Documentation/UnstableGrothendieckWittClassesDoc.m2:278:0.