Update to 2.0.0 tree from current Fremantle build

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

diff --git a/3rdparty/lapack/dtrtrs.c b/3rdparty/lapack/dtrtrs.c
new file mode 100644 (file)
index 0000000..6f76301
--- /dev/null
+++ b/3rdparty/lapack/dtrtrs.c
@@ -0,0 +1,170 @@
+#include "clapack.h"
+
+/* Table of constant values */
+
+static doublereal c_b12 = 1.;
+
+/* Subroutine */ int dtrtrs_(char *uplo, char *trans, char *diag, integer *n, 
+       integer *nrhs, doublereal *a, integer *lda, doublereal *b, integer *
+       ldb, integer *info)
+{
+    /* System generated locals */
+    integer a_dim1, a_offset, b_dim1, b_offset, i__1;
+
+    /* Local variables */
+    extern logical lsame_(char *, char *);
+    extern /* Subroutine */ int dtrsm_(char *, char *, char *, char *, 
+           integer *, integer *, doublereal *, doublereal *, integer *, 
+           doublereal *, integer *), xerbla_(
+           char *, integer *);
+    logical nounit;
+
+
+/*  -- LAPACK routine (version 3.1) -- */
+/*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/*     November 2006 */
+
+/*     .. Scalar Arguments .. */
+/*     .. */
+/*     .. Array Arguments .. */
+/*     .. */
+
+/*  Purpose */
+/*  ======= */
+
+/*  DTRTRS solves a triangular system of the form */
+
+/*     A * X = B  or  A**T * X = B, */
+
+/*  where A is a triangular matrix of order N, and B is an N-by-NRHS */
+/*  matrix.  A check is made to verify that A is nonsingular. */
+
+/*  Arguments */
+/*  ========= */
+
+/*  UPLO    (input) CHARACTER*1 */
+/*          = 'U':  A is upper triangular; */
+/*          = 'L':  A is lower triangular. */
+
+/*  TRANS   (input) CHARACTER*1 */
+/*          Specifies the form of the system of equations: */
+/*          = 'N':  A * X = B  (No transpose) */
+/*          = 'T':  A**T * X = B  (Transpose) */
+/*          = 'C':  A**H * X = B  (Conjugate transpose = Transpose) */
+
+/*  DIAG    (input) CHARACTER*1 */
+/*          = 'N':  A is non-unit triangular; */
+/*          = 'U':  A is unit triangular. */
+
+/*  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 triangular matrix A.  If UPLO = 'U', the leading N-by-N */
+/*          upper triangular part of the array A contains the upper */
+/*          triangular matrix, and the strictly lower triangular part of */
+/*          A is not referenced.  If UPLO = 'L', the leading N-by-N lower */
+/*          triangular part of the array A contains the lower triangular */
+/*          matrix, and the strictly upper triangular part of A is not */
+/*          referenced.  If DIAG = 'U', the diagonal elements of A are */
+/*          also not referenced and are assumed to be 1. */
+
+/*  LDA     (input) INTEGER */
+/*          The leading dimension of the array A.  LDA >= max(1,N). */
+
+/*  B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS) */
+/*          On entry, the right hand side matrix B. */
+/*          On exit, if INFO = 0, 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 */
+/*          > 0: if INFO = i, the i-th diagonal element of A is zero, */
+/*               indicating that the matrix is singular and the solutions */
+/*               X have not been computed. */
+
+/*  ===================================================================== */
+
+/*     .. Parameters .. */
+/*     .. */
+/*     .. Local Scalars .. */
+/*     .. */
+/*     .. External Functions .. */
+/*     .. */
+/*     .. External Subroutines .. */
+/*     .. */
+/*     .. Intrinsic Functions .. */
+/*     .. */
+/*     .. Executable Statements .. */
+
+/*     Test the input parameters. */
+
+    /* Parameter adjustments */
+    a_dim1 = *lda;
+    a_offset = 1 + a_dim1;
+    a -= a_offset;
+    b_dim1 = *ldb;
+    b_offset = 1 + b_dim1;
+    b -= b_offset;
+
+    /* Function Body */
+    *info = 0;
+    nounit = lsame_(diag, "N");
+    if (! lsame_(uplo, "U") && ! lsame_(uplo, "L")) {
+       *info = -1;
+    } else if (! lsame_(trans, "N") && ! lsame_(trans, 
+           "T") && ! lsame_(trans, "C")) {
+       *info = -2;
+    } else if (! nounit && ! lsame_(diag, "U")) {
+       *info = -3;
+    } else if (*n < 0) {
+       *info = -4;
+    } else if (*nrhs < 0) {
+       *info = -5;
+    } else if (*lda < max(1,*n)) {
+       *info = -7;
+    } else if (*ldb < max(1,*n)) {
+       *info = -9;
+    }
+    if (*info != 0) {
+       i__1 = -(*info);
+       xerbla_("DTRTRS", &i__1);
+       return 0;
+    }
+
+/*     Quick return if possible */
+
+    if (*n == 0) {
+       return 0;
+    }
+
+/*     Check for singularity. */
+
+    if (nounit) {
+       i__1 = *n;
+       for (*info = 1; *info <= i__1; ++(*info)) {
+           if (a[*info + *info * a_dim1] == 0.) {
+               return 0;
+           }
+/* L10: */
+       }
+    }
+    *info = 0;
+
+/*     Solve A * x = b  or  A' * x = b. */
+
+    dtrsm_("Left", uplo, trans, diag, n, nrhs, &c_b12, &a[a_offset], lda, &b[
+           b_offset], ldb);
+
+    return 0;
+
+/*     End of DTRTRS */
+
+} /* dtrtrs_ */