Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: ALGORITHM 937: MINRES-QLP for Singular Symmetric and Hermitian Linear
  Equations and Least-Squares Problems   We describe algorithm MINRES-QLP and its FORTRAN 90 implementation for
solving symmetric or Hermitian linear systems or least-squares problems. If the
system is singular, MINRES-QLP computes the unique minimum-length solution
(also known as the pseudoinverse solution), which generally eludes MINRES. In
all cases, it overcomes a potential instability in the original MINRES
algorithm. A positive-definite preconditioner may be supplied. Our FORTRAN 90
implementation illustrates a design pattern that allows users to make problem
data known to the solver but hidden and secure from other program units. In
particular, we circumvent the need for reverse communication. While we focus
here on a FORTRAN 90 implementation, we also provide and maintain MATLAB
versions of MINRES and MINRES-QLP.

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The categories of this paper are: cond-mat
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The categories of this paper are: hep-th
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The categories of this paper are: solv-int
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The categories of this paper are: q-fin
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The categories of this paper are: math-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex
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The categories of this paper are: astro-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: comp-gas
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The categories of this paper are: adap-org
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The categories of this paper are: chao-dyn
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The categories of this paper are: eess
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The categories of this paper are: nucl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: nlin