diff --git a/Basis_Function.py b/Basis_Function.py
index 1563cf823593312520ea758bc252a3af8ccdfe3e..e423aa8b8876851c301822e69be9e0df5347bf1d 100644
--- a/Basis_Function.py
+++ b/Basis_Function.py
@@ -162,6 +162,21 @@ class Basis:
         return np.array(list(map(np.float64, cell_averages)))
 
     def _calculate_reconstructions(self, projection):
+        """Calculate left and right reconstructions for a given projection.
+
+        Parameters
+        ----------
+        projection : ndarray
+            Matrix of projection for each polynomial degree.
+
+        Returns
+        -------
+        left_reconstruction: ndarray
+            List containing left reconstructions for given projection.
+        right_reconstruction: ndarray
+            List containing right reconstructions for given projection.
+
+        """
         left_reconstructions = calculate_approximate_solution(
             projection, np.array([-1]), self._polynomial_degree, self._basis)
         right_reconstructions = calculate_approximate_solution(