Update to 2.0.0 tree from current Fremantle build

[opencv] / 3rdparty / lapack / dgesv.c

diff --git a/3rdparty/lapack/dgesv.c b/3rdparty/lapack/dgesv.c
new file mode 100644 (file)
index 0000000..62ac831
--- /dev/null
+++ b/3rdparty/lapack/dgesv.c
@@ -0,0 +1,125 @@
+#include "clapack.h"
+
+/* Subroutine */ int dgesv_(integer *n, integer *nrhs, doublereal *a, integer 
+       *lda, integer *ipiv, doublereal *b, integer *ldb, integer *info)
+{
+    /* System generated locals */
+    integer a_dim1, a_offset, b_dim1, b_offset, i__1;
+
+    /* Local variables */
+    extern /* Subroutine */ int dgetrf_(integer *, integer *, doublereal *, 
+           integer *, integer *, integer *), xerbla_(char *, integer *), dgetrs_(char *, integer *, integer *, doublereal *, 
+           integer *, integer *, doublereal *, integer *, integer *);
+
+
+/*  -- LAPACK driver routine (version 3.1) -- */
+/*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/*     November 2006 */
+
+/*     .. Scalar Arguments .. */
+/*     .. */
+/*     .. Array Arguments .. */
+/*     .. */
+
+/*  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 .. */
+/*     .. */
+/*     .. Intrinsic Functions .. */
+/*     .. */
+/*     .. Executable Statements .. */
+
+/*     Test the input parameters. */
+
+    /* Parameter adjustments */
+    a_dim1 = *lda;
+    a_offset = 1 + a_dim1;
+    a -= a_offset;
+    --ipiv;
+    b_dim1 = *ldb;
+    b_offset = 1 + b_dim1;
+    b -= b_offset;
+
+    /* Function Body */
+    *info = 0;
+    if (*n < 0) {
+       *info = -1;
+    } else if (*nrhs < 0) {
+       *info = -2;
+    } else if (*lda < max(1,*n)) {
+       *info = -4;
+    } else if (*ldb < max(1,*n)) {
+       *info = -7;
+    }
+    if (*info != 0) {
+       i__1 = -(*info);
+       xerbla_("DGESV ", &i__1);
+       return 0;
+    }
+
+/*     Compute the LU factorization of A. */
+
+    dgetrf_(n, n, &a[a_offset], lda, &ipiv[1], info);
+    if (*info == 0) {
+
+/*        Solve the system A*X = B, overwriting B with X. */
+
+       dgetrs_("No transpose", n, nrhs, &a[a_offset], lda, &ipiv[1], &b[
+               b_offset], ldb, info);
+    }
+    return 0;
+
+/*     End of DGESV */
+
+} /* dgesv_ */