Various documentation updates:
- update the tutorial
- update doc of deprecated cwise function
- update cwise doc snippets
diff --git a/doc/snippets/Cwise_abs2.cpp b/doc/snippets/Cwise_abs2.cpp
index 3b338af..2c4f9b3 100644
--- a/doc/snippets/Cwise_abs2.cpp
+++ b/doc/snippets/Cwise_abs2.cpp
@@ -1,2 +1,2 @@
-Vector3d v(1,-2,-3);
-cout << v.cwise().abs2() << endl;
+Array3d v(1,-2,-3);
+cout << v.abs2() << endl;