Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Littlewood's algorithm and quaternion matrices   A strengthened form of Schur's triangularization theorem is given for
quaternion matrices with real spectrum (for complex matrices it was given by
Littlewood). Littlewood's algorithm for reducing a complex matrix to a
canonical form under unitary similarity is extended to quaternion matrices
whose eigenvalues have geometric multiplicity 1.

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The categories of this paper are: math-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: atom-ph
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The categories of this paper are: cs
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The categories of this paper are: astro-ph
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The categories of this paper are: funct-an
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The categories of this paper are: hep-th
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The categories of this paper are: eess
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The categories of this paper are: adap-org
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
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The categories of this paper are: physics
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The categories of this paper are: cond-mat