LAPACK 3.11.0
LAPACK: Linear Algebra PACKage

◆ dgesc2()

subroutine dgesc2 ( integer  N,
double precision, dimension( lda, * )  A,
integer  LDA,
double precision, dimension( * )  RHS,
integer, dimension( * )  IPIV,
integer, dimension( * )  JPIV,
double precision  SCALE 
)

DGESC2 solves a system of linear equations using the LU factorization with complete pivoting computed by sgetc2.

Download DGESC2 + dependencies [TGZ] [ZIP] [TXT]

Purpose:
 DGESC2 solves a system of linear equations

           A * X = scale* RHS

 with a general N-by-N matrix A using the LU factorization with
 complete pivoting computed by DGETC2.
Parameters
[in]N
          N is INTEGER
          The order of the matrix A.
[in]A
          A is DOUBLE PRECISION array, dimension (LDA,N)
          On entry, the  LU part of the factorization of the n-by-n
          matrix A computed by DGETC2:  A = P * L * U * Q
[in]LDA
          LDA is INTEGER
          The leading dimension of the array A.  LDA >= max(1, N).
[in,out]RHS
          RHS is DOUBLE PRECISION array, dimension (N).
          On entry, the right hand side vector b.
          On exit, the solution vector X.
[in]IPIV
          IPIV is INTEGER array, dimension (N).
          The pivot indices; for 1 <= i <= N, row i of the
          matrix has been interchanged with row IPIV(i).
[in]JPIV
          JPIV is INTEGER array, dimension (N).
          The pivot indices; for 1 <= j <= N, column j of the
          matrix has been interchanged with column JPIV(j).
[out]SCALE
          SCALE is DOUBLE PRECISION
          On exit, SCALE contains the scale factor. SCALE is chosen
          0 <= SCALE <= 1 to prevent overflow in the solution.
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Contributors:
Bo Kagstrom and Peter Poromaa, Department of Computing Science, Umea University, S-901 87 Umea, Sweden.