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diff --git a/3rdparty/lapack/slasq1.c b/3rdparty/lapack/slasq1.c
new file mode 100644
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+++ b/3rdparty/lapack/slasq1.c
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+#include "clapack.h"
+
+/* Table of constant values */
+
+static integer c__1 = 1;
+static integer c__2 = 2;
+static integer c__0 = 0;
+
+/* Subroutine */ int slasq1_(integer *n, real *d__, real *e, real *work, 
+	integer *info)
+{
+    /* System generated locals */
+    integer i__1, i__2;
+    real r__1, r__2, r__3;
+
+    /* Builtin functions */
+    double sqrt(doublereal);
+
+    /* Local variables */
+    integer i__;
+    real eps;
+    extern /* Subroutine */ int slas2_(real *, real *, real *, real *, real *)
+	    ;
+    real scale;
+    integer iinfo;
+    real sigmn, sigmx;
+    extern /* Subroutine */ int scopy_(integer *, real *, integer *, real *, 
+	    integer *), slasq2_(integer *, real *, integer *);
+    extern doublereal slamch_(char *);
+    real safmin;
+    extern /* Subroutine */ int xerbla_(char *, integer *), slascl_(
+	    char *, integer *, integer *, real *, real *, integer *, integer *
+, real *, integer *, integer *), slasrt_(char *, integer *
+, real *, integer *);
+
+
+/*  -- LAPACK routine (version 3.1) -- */
+/*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/*     November 2006 */
+
+/*     .. Scalar Arguments .. */
+/*     .. */
+/*     .. Array Arguments .. */
+/*     .. */
+
+/*  Purpose */
+/*  ======= */
+
+/*  SLASQ1 computes the singular values of a real N-by-N bidiagonal */
+/*  matrix with diagonal D and off-diagonal E. The singular values */
+/*  are computed to high relative accuracy, in the absence of */
+/*  denormalization, underflow and overflow. The algorithm was first */
+/*  presented in */
+
+/*  "Accurate singular values and differential qd algorithms" by K. V. */
+/*  Fernando and B. N. Parlett, Numer. Math., Vol-67, No. 2, pp. 191-230, */
+/*  1994, */
+
+/*  and the present implementation is described in "An implementation of */
+/*  the dqds Algorithm (Positive Case)", LAPACK Working Note. */
+
+/*  Arguments */
+/*  ========= */
+
+/*  N     (input) INTEGER */
+/*        The number of rows and columns in the matrix. N >= 0. */
+
+/*  D     (input/output) REAL array, dimension (N) */
+/*        On entry, D contains the diagonal elements of the */
+/*        bidiagonal matrix whose SVD is desired. On normal exit, */
+/*        D contains the singular values in decreasing order. */
+
+/*  E     (input/output) REAL array, dimension (N) */
+/*        On entry, elements E(1:N-1) contain the off-diagonal elements */
+/*        of the bidiagonal matrix whose SVD is desired. */
+/*        On exit, E is overwritten. */
+
+/*  WORK  (workspace) REAL array, dimension (4*N) */
+
+/*  INFO  (output) INTEGER */
+/*        = 0: successful exit */
+/*        < 0: if INFO = -i, the i-th argument had an illegal value */
+/*        > 0: the algorithm failed */
+/*             = 1, a split was marked by a positive value in E */
+/*             = 2, current block of Z not diagonalized after 30*N */
+/*                  iterations (in inner while loop) */
+/*             = 3, termination criterion of outer while loop not met */
+/*                  (program created more than N unreduced blocks) */
+
+/*  ===================================================================== */
+
+/*     .. Parameters .. */
+/*     .. */
+/*     .. Local Scalars .. */
+/*     .. */
+/*     .. External Subroutines .. */
+/*     .. */
+/*     .. External Functions .. */
+/*     .. */
+/*     .. Intrinsic Functions .. */
+/*     .. */
+/*     .. Executable Statements .. */
+
+    /* Parameter adjustments */
+    --work;
+    --e;
+    --d__;
+
+    /* Function Body */
+    *info = 0;
+    if (*n < 0) {
+	*info = -2;
+	i__1 = -(*info);
+	xerbla_("SLASQ1", &i__1);
+	return 0;
+    } else if (*n == 0) {
+	return 0;
+    } else if (*n == 1) {
+	d__[1] = dabs(d__[1]);
+	return 0;
+    } else if (*n == 2) {
+	slas2_(&d__[1], &e[1], &d__[2], &sigmn, &sigmx);
+	d__[1] = sigmx;
+	d__[2] = sigmn;
+	return 0;
+    }
+
+/*     Estimate the largest singular value. */
+
+    sigmx = 0.f;
+    i__1 = *n - 1;
+    for (i__ = 1; i__ <= i__1; ++i__) {
+	d__[i__] = (r__1 = d__[i__], dabs(r__1));
+/* Computing MAX */
+	r__2 = sigmx, r__3 = (r__1 = e[i__], dabs(r__1));
+	sigmx = dmax(r__2,r__3);
+/* L10: */
+    }
+    d__[*n] = (r__1 = d__[*n], dabs(r__1));
+
+/*     Early return if SIGMX is zero (matrix is already diagonal). */
+
+    if (sigmx == 0.f) {
+	slasrt_("D", n, &d__[1], &iinfo);
+	return 0;
+    }
+
+    i__1 = *n;
+    for (i__ = 1; i__ <= i__1; ++i__) {
+/* Computing MAX */
+	r__1 = sigmx, r__2 = d__[i__];
+	sigmx = dmax(r__1,r__2);
+/* L20: */
+    }
+
+/*     Copy D and E into WORK (in the Z format) and scale (squaring the */
+/*     input data makes scaling by a power of the radix pointless). */
+
+    eps = slamch_("Precision");
+    safmin = slamch_("Safe minimum");
+    scale = sqrt(eps / safmin);
+    scopy_(n, &d__[1], &c__1, &work[1], &c__2);
+    i__1 = *n - 1;
+    scopy_(&i__1, &e[1], &c__1, &work[2], &c__2);
+    i__1 = (*n << 1) - 1;
+    i__2 = (*n << 1) - 1;
+    slascl_("G", &c__0, &c__0, &sigmx, &scale, &i__1, &c__1, &work[1], &i__2, 
+	    &iinfo);
+
+/*     Compute the q's and e's. */
+
+    i__1 = (*n << 1) - 1;
+    for (i__ = 1; i__ <= i__1; ++i__) {
+/* Computing 2nd power */
+	r__1 = work[i__];
+	work[i__] = r__1 * r__1;
+/* L30: */
+    }
+    work[*n * 2] = 0.f;
+
+    slasq2_(n, &work[1], info);
+
+    if (*info == 0) {
+	i__1 = *n;
+	for (i__ = 1; i__ <= i__1; ++i__) {
+	    d__[i__] = sqrt(work[i__]);
+/* L40: */
+	}
+	slascl_("G", &c__0, &c__0, &scale, &sigmx, n, &c__1, &d__[1], n, &
+		iinfo);
+    }
+
+    return 0;
+
+/*     End of SLASQ1 */
+
+} /* slasq1_ */