.ThermoSysPro.Properties.WaterSteam.IF97_packages.IF97_wAJ.Spline_Utilities.Modelica_Interpolation.Utilities.dgesv

Information

Lapack documentation:  
    Purpose  
    =======  
    DGESV computes the solution to a real system of linear equations  
       A * X = B,  
    where A is an N-by-N matrix and X and B are N-by-NRHS matrices.  
    The LU decomposition with partial pivoting and row interchanges is  
    used to factor A as  
       A = P * L * U,  
    where P is a permutation matrix, L is unit lower triangular, and U is  

    upper triangular.  The factored form of A is then used to solve the  
    system of equations A * X = B.  
    Arguments  
    =========  
    N       (input) INTEGER  
            The number of linear equations, i.e., 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/output) DOUBLE PRECISION array, dimension (LDA,N)  
            On entry, the N-by-N coefficient matrix A.  
            On exit, the factors L and U from the factorization  
            A = P*L*U; the unit diagonal elements of L are not stored.  
    LDA     (input) INTEGER  
            The leading dimension of the array A.  LDA >= max(1,N).  
    IPIV    (output) INTEGER array, dimension (N)  
            The pivot indices that define the permutation matrix P;  
            row i of the matrix was interchanged with row IPIV(i).  
    B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)  
            On entry, the N-by-NRHS matrix of right hand side matrix B.  
            On exit, if INFO = 0, the N-by-NRHS 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  
            > 0:  if INFO = i, U(i,i) is exactly zero.  The factorization  

                  has been completed, but the factor U is exactly  
                  singular, so the solution could not be computed.  
## Copyright © EDF 2002 - 2025

## ThermoSysPro Version 4.2

              

Interface

function dgesv
  extends Modelica.Icons.Function;
  input Real A[:, size(A, 1)];
  input Real B[size(A, 1), :];
  output Real X[size(A, 1), size(B, 2)] = B;
  output Integer info;
end dgesv;