1SGESC2(1)           LAPACK auxiliary routine (version 3.1)           SGESC2(1)
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NAME

6       SGESC2 - a system of linear equations   A * X = scale* RHS  with a gen‐
7       eral N-by-N matrix A using the LU factorization with complete  pivoting
8       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

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

53       Based on contributions by
54          Bo Kagstrom and Peter Poromaa, Department of Computing Science,
55          Umea University, S-901 87 Umea, Sweden.
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60 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                       SGESC2(1)