Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Darboux transformations for multivariate orthogonal polynomials   Darboux transformations for polynomial perturbations of a real multivariate
measure are found. The 1D Christoffel formula is extended to the
multidimensional realm: multivariate orthogonal polynomials are expressed in
terms of last quasi-determinants and sample matrices. The coefficients of these
matrices are the original orthogonal polynomials evaluated at a set of nodes,
which is supposed to be poised. A discussion for the existence of poised sets
is given in terms of algebraic hypersufaces in the complex affine space.

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The categories of this paper are: acc-phys
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The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
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The categories of this paper are: stat
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The categories of this paper are: adap-org
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The categories of this paper are: hep-th
3
The categories of this paper are: physics