Extend documentation and add examples for ComplexEigenSolver.
diff --git a/doc/snippets/ComplexEigenSolver_eigenvalues.cpp b/doc/snippets/ComplexEigenSolver_eigenvalues.cpp
new file mode 100644
index 0000000..1afa8b0
--- /dev/null
+++ b/doc/snippets/ComplexEigenSolver_eigenvalues.cpp
@@ -0,0 +1,4 @@
+MatrixXcf ones = MatrixXcf::Ones(3,3);
+ComplexEigenSolver<MatrixXcf> ces(ones);
+cout << "The eigenvalues of the 3x3 matrix of ones are:" 
+     << endl << ces.eigenvalues() << endl;