Add some more examples for the API documentation.
The only missing examples now are for homogeneous() and hnormalized();
I don't know what they're used for ...
diff --git a/doc/snippets/DirectionWise_replicate.cpp b/doc/snippets/DirectionWise_replicate.cpp
new file mode 100644
index 0000000..d92d4a3
--- /dev/null
+++ b/doc/snippets/DirectionWise_replicate.cpp
@@ -0,0 +1,4 @@
+MatrixXi m = MatrixXi::Random(2,3);
+cout << "Here is the matrix m:" << endl << m << endl;
+cout << "m.colwise().replicate<3>() = ..." << endl;
+cout << m.colwise().replicate<3>() << endl;