1CGETRS(1)                LAPACK routine (version 3.1)                CGETRS(1)
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NAME

6       CGETRS - a system of linear equations  A * X = B, A**T * X = B, or A**H
7       * X = B with a general N-by-N matrix A using the LU factorization  com‐
8       puted by CGETRF
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SYNOPSIS

11       SUBROUTINE CGETRS( TRANS, N, NRHS, A, LDA, IPIV, B, LDB, INFO )
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13           CHARACTER      TRANS
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15           INTEGER        INFO, LDA, LDB, N, NRHS
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17           INTEGER        IPIV( * )
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19           COMPLEX        A( LDA, * ), B( LDB, * )
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PURPOSE

22       CGETRS solves a system of linear equations
23          A  *  X  = B,  A**T * X = B,  or  A**H * X = B with a general N-by-N
24       matrix A using the LU factorization computed by CGETRF.
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ARGUMENTS

28       TRANS   (input) CHARACTER*1
29               Specifies the form of the system of equations:
30               = 'N':  A * X = B     (No transpose)
31               = 'T':  A**T * X = B  (Transpose)
32               = 'C':  A**H * X = B  (Conjugate transpose)
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34       N       (input) INTEGER
35               The order of the matrix A.  N >= 0.
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37       NRHS    (input) INTEGER
38               The number of right hand sides, i.e., the number of columns  of
39               the matrix B.  NRHS >= 0.
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41       A       (input) COMPLEX array, dimension (LDA,N)
42               The  factors  L  and U from the factorization A = P*L*U as com‐
43               puted by CGETRF.
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45       LDA     (input) INTEGER
46               The leading dimension of the array A.  LDA >= max(1,N).
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48       IPIV    (input) INTEGER array, dimension (N)
49               The pivot indices from CGETRF; for 1<=i<=N, row i of the matrix
50               was interchanged with row IPIV(i).
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52       B       (input/output) COMPLEX array, dimension (LDB,NRHS)
53               On  entry, the right hand side matrix B.  On exit, the solution
54               matrix X.
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56       LDB     (input) INTEGER
57               The leading dimension of the array B.  LDB >= max(1,N).
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59       INFO    (output) INTEGER
60               = 0:  successful exit
61               < 0:  if INFO = -i, the i-th argument had an illegal value
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65 LAPACK routine (version 3.1)    November 2006                       CGETRS(1)
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