diff --git a/doc/snippets/MatrixBase_diagonal.cpp b/doc/snippets/MatrixBase_diagonal.cpp
new file mode 100644
index 0000000..cd63413
--- /dev/null
+++ b/doc/snippets/MatrixBase_diagonal.cpp
@@ -0,0 +1,4 @@
+Matrix3i m = Matrix3i::Random();
+cout << "Here is the matrix m:" << endl << m << endl;
+cout << "Here are the coefficients on the main diagonal of m:" << endl
+     << m.diagonal() << endl;