Update to 2.0.0 tree from current Fremantle build

[opencv] / 3rdparty / lapack / dlapy2.c

diff --git a/3rdparty/lapack/dlapy2.c b/3rdparty/lapack/dlapy2.c
new file mode 100644 (file)
index 0000000..82b91d3
--- /dev/null
+++ b/3rdparty/lapack/dlapy2.c
@@ -0,0 +1,60 @@
+#include "clapack.h"
+
+doublereal dlapy2_(doublereal *x, doublereal *y)
+{
+    /* System generated locals */
+    doublereal ret_val, d__1;
+
+    /* Builtin functions */
+    double sqrt(doublereal);
+
+    /* Local variables */
+    doublereal w, z__, xabs, yabs;
+
+
+/*  -- LAPACK auxiliary routine (version 3.1) -- */
+/*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/*     November 2006 */
+
+/*     .. Scalar Arguments .. */
+/*     .. */
+
+/*  Purpose */
+/*  ======= */
+
+/*  DLAPY2 returns sqrt(x**2+y**2), taking care not to cause unnecessary */
+/*  overflow. */
+
+/*  Arguments */
+/*  ========= */
+
+/*  X       (input) DOUBLE PRECISION */
+/*  Y       (input) DOUBLE PRECISION */
+/*          X and Y specify the values x and y. */
+
+/*  ===================================================================== */
+
+/*     .. Parameters .. */
+/*     .. */
+/*     .. Local Scalars .. */
+/*     .. */
+/*     .. Intrinsic Functions .. */
+/*     .. */
+/*     .. Executable Statements .. */
+
+    xabs = abs(*x);
+    yabs = abs(*y);
+    w = max(xabs,yabs);
+    z__ = min(xabs,yabs);
+    if (z__ == 0.) {
+       ret_val = w;
+    } else {
+/* Computing 2nd power */
+       d__1 = z__ / w;
+       ret_val = w * sqrt(d__1 * d__1 + 1.);
+    }
+    return ret_val;
+
+/*     End of DLAPY2 */
+
+} /* dlapy2_ */