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kalmarek / SymbolicWedderburn.jl

Amazing package to compute decompositions into irreducibles of explicit group representations and the Wedderburn decomposition for endomorphisms thereof!
MIT License
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Can we compute invariant vectors using the trivial character + associated projection? #43

Closed kalmarek closed 2 years ago

kalmarek commented 2 years ago

@thinh-le

Note that we also need to make sure that invariant vectors are orthogonal

kalmarek commented 2 years ago

implemented in #44 although computing isotypical projection when acting on basis of length in millions (rref of matrix with million rows) is always going to be slow. The best course of action in case of permutation + sign action is to implement invariant_vectors similarly as it is done for ByPermutations https://github.com/kalmarek/SymbolicWedderburn.jl/blob/fe363d2e269602dd487d9f33665141e0cbdfc87b/src/wedderburn_decomposition.jl#L128