added 2geom/utils.cpp - unused, but useful

diff --git a/src/2geom/utils.cpp b/src/2geom/utils.cpp
new file mode 100644 (file)
index 0000000..5797185
--- /dev/null
+++ b/src/2geom/utils.cpp
@@ -0,0 +1,87 @@
+/** Various utility functions.
+ *
+ * Copyright 2008 Marco Cecchetti <mrcekets at gmail.com>
+ * Copyright 2007 Johan Engelen <goejendaagh@zonnet.nl>
+ * Copyright 2006 Michael G. Sloan <mgsloan@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it either under the terms of the GNU Lesser General Public
+ * License version 2.1 as published by the Free Software Foundation
+ * (the "LGPL") or, at your option, under the terms of the Mozilla
+ * Public License Version 1.1 (the "MPL"). If you do not alter this
+ * notice, a recipient may use your version of this file under either
+ * the MPL or the LGPL.
+ *
+ * You should have received a copy of the LGPL along with this library
+ * in the file COPYING-LGPL-2.1; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * You should have received a copy of the MPL along with this library
+ * in the file COPYING-MPL-1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License
+ * Version 1.1 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
+ * OF ANY KIND, either express or implied. See the LGPL or the MPL for
+ * the specific language governing rights and limitations.
+ *
+ */
+
+
+#include <2geom/utils.h>
+
+
+namespace Geom 
+{
+
+// return a vector that contains all the binomial coefficients of degree n 
+void binomial_coefficients(std::vector<size_t>& bc, size_t n)
+{
+    size_t s = n+1;
+    bc.clear();
+    bc.resize(s);
+    bc[0] = 1;
+    size_t k;
+    for (size_t i = 1; i < n; ++i)
+    {
+        k = i >> 1;
+        if (i & 1u)
+        {
+            bc[k+1] = bc[k] << 1;
+        }
+        for (size_t j = k; j > 0; --j)
+        {
+            bc[j] += bc[j-1];
+        }
+    }
+    s >>= 1;
+    for (size_t i = 0; i < s; ++i)
+    {
+        bc[n-i] = bc[i];
+    }
+}
+
+} // end namespace Geom
+
+
+
+
+
+
+
+
+
+
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :