Squashed 'third_party/boostorg/ublas/' content from commit e8607b3

Change-Id: Ia06afd642157a24e17fa9ddea28fb8601810b78e
git-subtree-dir: third_party/boostorg/ublas
git-subtree-split: e8607b3eea238e590eca93bfe498c21f470155c1
diff --git a/doc/samples/triangular_matrix.cpp b/doc/samples/triangular_matrix.cpp
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+//
+//  Copyright (c) 2000-2002
+//  Joerg Walter, Mathias Koch
+//
+//  Distributed under the Boost Software License, Version 1.0. (See
+//  accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+//
+//  The authors gratefully acknowledge the support of
+//  GeNeSys mbH & Co. KG in producing this work.
+//
+
+#include <boost/numeric/ublas/triangular.hpp>
+#include <boost/numeric/ublas/io.hpp>
+
+int main () {
+    using namespace boost::numeric::ublas;
+    triangular_matrix<double, lower> ml (3, 3);
+    for (unsigned i = 0; i < ml.size1 (); ++ i)
+        for (unsigned j = 0; j <= i; ++ j)
+            ml (i, j) = 3 * i + j;
+    std::cout << ml << std::endl;
+    triangular_matrix<double, upper> mu (3, 3);
+    for (unsigned i = 0; i < mu.size1 (); ++ i)
+        for (unsigned j = i; j < mu.size2 (); ++ j)
+            mu (i, j) = 3 * i + j;
+    std::cout << mu << std::endl;
+}
+