1ZGESC2(1) LAPACK auxiliary routine (version 3.2) ZGESC2(1)
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6 ZGESC2 - 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 ZGETC2
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11 SUBROUTINE ZGESC2( N, A, LDA, RHS, IPIV, JPIV, SCALE )
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13 INTEGER LDA, N
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15 DOUBLE PRECISION SCALE
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17 INTEGER IPIV( * ), JPIV( * )
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19 COMPLEX*16 A( LDA, * ), RHS( * )
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22 ZGESC2 solves a system of linear equations
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25 N (input) INTEGER
26 The number of columns of the matrix A.
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28 A (input) COMPLEX*16 array, dimension (LDA, N)
29 On entry, the LU part of the factorization of the n-by-n
30 matrix A computed by ZGETC2: 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) COMPLEX*16 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) DOUBLE PRECISION
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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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 ZGESC2(1)