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diff --git a/src/fortran/lapack/dgesv.f b/src/fortran/lapack/dgesv.f
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+      SUBROUTINE DGESV( N, NRHS, A, LDA, IPIV, B, LDB, INFO )
+*
+*  -- LAPACK driver routine (version 3.1) --
+*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
+*     November 2006
+*
+*     .. Scalar Arguments ..
+      INTEGER            INFO, LDA, LDB, N, NRHS
+*     ..
+*     .. Array Arguments ..
+      INTEGER            IPIV( * )
+      DOUBLE PRECISION   A( LDA, * ), B( LDB, * )
+*     ..
+*
+*  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.
+*
+*  =====================================================================
+*
+*     .. External Subroutines ..
+      EXTERNAL           DGETRF, DGETRS, XERBLA
+*     ..
+*     .. Intrinsic Functions ..
+      INTRINSIC          MAX
+*     ..
+*     .. Executable Statements ..
+*
+*     Test the input parameters.
+*
+      INFO = 0
+      IF( N.LT.0 ) THEN
+         INFO = -1
+      ELSE IF( NRHS.LT.0 ) THEN
+         INFO = -2
+      ELSE IF( LDA.LT.MAX( 1, N ) ) THEN
+         INFO = -4
+      ELSE IF( LDB.LT.MAX( 1, N ) ) THEN
+         INFO = -7
+      END IF
+      IF( INFO.NE.0 ) THEN
+         CALL XERBLA( 'DGESV ', -INFO )
+         RETURN
+      END IF
+*
+*     Compute the LU factorization of A.
+*
+      CALL DGETRF( N, N, A, LDA, IPIV, INFO )
+      IF( INFO.EQ.0 ) THEN
+*
+*        Solve the system A*X = B, overwriting B with X.
+*
+         CALL DGETRS( 'No transpose', N, NRHS, A, LDA, IPIV, B, LDB,
+     $                INFO )
+      END IF
+      RETURN
+*
+*     End of DGESV
+*
+      END