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WeylGroups :: isRoot(RootSystem,Weight)

isRoot(RootSystem,Weight) -- check whether a weight is a positive root

Synopsis

Description

i1 : R=rootSystemE(6)

o1 = RootSystem{...8...}

o1 : RootSystem
i2 : p=simpleRoot(R,1)

o2 = |  2 |
     |  0 |
     | -1 |
     |  0 |
     |  0 |
     |  0 |

o2 : Root
i3 : isPositiveRoot(R,-p)

o3 = false
i4 : isRoot(R,-p)

o4 = true