.Modelica.Math.Matrices.LAPACK.dgetrs

Information

Lapack documentation
    Purpose
    =======

    DGETRS solves a system of linear equations
       A * X = B  or  A' * X = B
    with a general N-by-N matrix A using the LU factorization computed
    by DGETRF.

    Arguments
    =========

    TRANS   (input) CHARACTER*1
            Specifies the form of the system of equations:
            = 'N':  A * X = B  (No transpose)
            = 'T':  A'* X = B  (Transpose)
            = 'C':  A'* X = B  (Conjugate transpose = Transpose)

    N       (input) INTEGER
            The order of the matrix A.  N >= 0.

    NRHS    (input) INTEGER
            The number of right hand sides, i.e., the number of columns
            of the matrix B.  NRHS >= 0.

    A       (input) DOUBLE PRECISION array, dimension (LDA,N)
            The factors L and U from the factorization A = P*L*U
            as computed by DGETRF.

    LDA     (input) INTEGER
            The leading dimension of the array A.  LDA >= max(1,N).

    IPIV    (input) INTEGER array, dimension (N)
            The pivot indices from DGETRF; for 1<=i<=N, row i of the
            matrix was interchanged with row IPIV(i).

    B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)
            On entry, the right hand side matrix B.
            On exit, the solution matrix X.

    LDB     (input) INTEGER
            The leading dimension of the array B.  LDB >= max(1,N).

    INFO    (output) INTEGER
            = 0:  successful exit
            < 0:  if INFO = -i, the i-th argument had an illegal value

Interface

pure function dgetrs
  extends Modelica.Icons.Function;
  input Real LU[:, size(LU, 1)] "LU factorization of dgetrf of a square matrix";
  input Integer pivots[size(LU, 1)] "Pivot vector of dgetrf";
  input Real B[size(LU, 1), :] "Right hand side matrix B";
  output Real X[size(B, 1), size(B, 2)] = B "Solution matrix X";
  output Integer info;
end dgetrs;