1SGESC2(1)           LAPACK auxiliary routine (version 3.2)           SGESC2(1)
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NAME

6       SGESC2 - solves a system of linear equations   A * X = scale* RHS  with
7       a general N-by-N matrix A using the LU factorization with complete piv‐
8       oting computed by SGETC2
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SYNOPSIS

11       SUBROUTINE SGESC2( N, A, LDA, RHS, IPIV, JPIV, SCALE )
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13           INTEGER        LDA, N
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15           REAL           SCALE
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17           INTEGER        IPIV( * ), JPIV( * )
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19           REAL           A( LDA, * ), RHS( * )
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PURPOSE

22       SGESC2 solves a system of linear equations
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ARGUMENTS

25       N       (input) INTEGER
26               The order of the matrix A.
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28       A       (input) REAL array, dimension (LDA,N)
29               On  entry,  the   LU  part  of  the factorization of the n-by-n
30               matrix A computed by SGETC2:  A = P * L * U * Q
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32       LDA     (input) INTEGER
33               The leading dimension of the array A.  LDA >= max(1, N).
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35       RHS     (input/output) REAL array, dimension (N).
36               On entry, the right hand side vector b.  On exit, the  solution
37               vector X.
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39       IPIV    (input) INTEGER array, dimension (N).
40               The  pivot  indices;  for  1 <= i <= N, row i of the matrix has
41               been interchanged with row IPIV(i).
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43       JPIV    (input) INTEGER array, dimension (N).
44               The pivot indices; for 1 <= j <= N, column j of the matrix  has
45               been interchanged with column JPIV(j).
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47       SCALE    (output) REAL
48                On exit, SCALE contains the scale factor. SCALE is chosen 0 <=
49                SCALE <= 1 to prevent owerflow in the solution.
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FURTHER DETAILS

52       Based on contributions by
53          Bo Kagstrom and Peter Poromaa, Department of Computing Science,
54          Umea University, S-901 87 Umea, Sweden.
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58 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                       SGESC2(1)
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