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*> \brief \b SLACON estimates the 1-norm of a square matrix, using reverse communication for evaluating matrix-vector products.
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* =========== DOCUMENTATION ===========
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* Online html documentation available at
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* http://www.netlib.org/lapack/explore-html/
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*> Download SLACON + dependencies
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/slacon.f">
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/slacon.f">
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/slacon.f">
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* SUBROUTINE SLACON( N, V, X, ISGN, EST, KASE )
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* .. Scalar Arguments ..
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* .. Array Arguments ..
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*> SLACON estimates the 1-norm of a square, real matrix A.
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*> Reverse communication is used for evaluating matrix-vector products.
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*> The order of the matrix. N >= 1.
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*> V is REAL array, dimension (N)
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*> On the final return, V = A*W, where EST = norm(V)/norm(W)
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*> (W is not returned).
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*> X is REAL array, dimension (N)
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*> On an intermediate return, X should be overwritten by
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*> A**T * X, if KASE=2,
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*> and SLACON must be re-called with all the other parameters
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*> ISGN is INTEGER array, dimension (N)
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*> On entry with KASE = 1 or 2 and JUMP = 3, EST should be
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*> unchanged from the previous call to SLACON.
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*> On exit, EST is an estimate (a lower bound) for norm(A).
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*> \param[in,out] KASE
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*> On the initial call to SLACON, KASE should be 0.
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*> On an intermediate return, KASE will be 1 or 2, indicating
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*> whether X should be overwritten by A * X or A**T * X.
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*> On the final return from SLACON, KASE will again be 0.
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*> \author Univ. of Tennessee
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*> \author Univ. of California Berkeley
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*> \author Univ. of Colorado Denver
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*> \date September 2012
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*> \ingroup realOTHERauxiliary
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*> \par Contributors:
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*> Nick Higham, University of Manchester. \n
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*> Originally named SONEST, dated March 16, 1988.
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*> N.J. Higham, "FORTRAN codes for estimating the one-norm of
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*> a real or complex matrix, with applications to condition estimation",
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*> ACM Trans. Math. Soft., vol. 14, no. 4, pp. 381-396, December 1988.
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* =====================================================================
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SUBROUTINE SLACON( N, V, X, ISGN, EST, KASE )
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* -- LAPACK auxiliary routine (version 2.0) --
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* Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
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* Courant Institute, Argonne National Lab, and Rice University
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* -- LAPACK auxiliary routine (version 3.4.2) --
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* -- LAPACK is a software package provided by Univ. of Tennessee, --
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* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
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* .. Scalar Arguments ..
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REAL V( * ), X( * )
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* $Id: slacon.f 19697 2010-10-29 16:57:34Z d3y133 $
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* SLACON estimates the 1-norm of a square, real matrix A.
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* Reverse communication is used for evaluating matrix-vector products.
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* The order of the matrix. N >= 1.
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* V (workspace) REAL array, dimension (N)
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* On the final return, V = A*W, where EST = norm(V)/norm(W)
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* (W is not returned).
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* X (input/output) REAL array, dimension (N)
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* On an intermediate return, X should be overwritten by
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* and SLACON must be re-called with all the other parameters
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* ISGN (workspace) INTEGER array, dimension (N)
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* An estimate (a lower bound) for norm(A).
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* KASE (input/output) INTEGER
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* On the initial call to SLACON, KASE should be 0.
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* On an intermediate return, KASE will be 1 or 2, indicating
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* whether X should be overwritten by A * X or A' * X.
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* On the final return from SLACON, KASE will again be 0.
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* Contributed by Nick Higham, University of Manchester.
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* Originally named SONEST, dated March 16, 1988.
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* Reference: N.J. Higham, "FORTRAN codes for estimating the one-norm of
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* a real or complex matrix, with applications to condition estimation",
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* ACM Trans. Math. Soft., vol. 14, no. 4, pp. 381-396, December 1988.
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* =====================================================================
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* .. Parameters ..