Add depth for tree

mapytex/calculus/core/tree.py

@@ -361,9 +361,6 @@ class Tree(object):
 
         :example:
 
-        >>> nested_par = ("+", (
-        ...    ("*", (3, 4)),
-        ...    2))
         >>> t = Tree.from_str("3*4+2")
         >>> [l for l in t.get_leafs()]
         [3, 4, 2]
@@ -387,17 +384,10 @@ class Tree(object):
 
         :example:
 
-        >>> nested_par = ("+", (
+        >>> t = Tree.from_str('3*4+2')
-        ...    ("*", (3, 4)),
-        ...    2))
-        >>> t = Tree.from_nested_parenthesis(nested_par)
         >>> [l for l in t.get_nodes()]
         ['+', '*']
-        >>> nested_par = ("+", (
+        >>> t = Tree.from_str('3*4+3*4')
-        ...    ("*", (3, 4)),
-        ...    ("*", (3, 4))
-        ...    ))
-        >>> t = Tree.from_nested_parenthesis(nested_par)
         >>> [l for l in t.get_nodes()]
         ['+', '*', '*']
         """
@@ -411,6 +401,43 @@ class Tree(object):
         except AttributeError:
             pass
 
+    def depth(self):
+        """ Return the depth of the tree
+
+        :example:
+
+        >>> nested_par = ("+", (1, 2))
+        >>> t = Tree.from_nested_parenthesis(nested_par)
+        >>> t.depth()
+        1
+        >>> nested_par = ("+", (
+        ...    ("*", (3, 4)),
+        ...    2))
+        >>> t = Tree.from_nested_parenthesis(nested_par)
+        >>> t.depth()
+        2
+        >>> nested_par = ("+", (
+        ...    ("*", (3,
+        ...        ("/", (4, 4))
+        ...        )),
+        ...    2))
+        >>> t = Tree.from_nested_parenthesis(nested_par)
+        >>> t.depth()
+        3
+
+        """
+        try:
+            l_depth = self.left_value.depth()
+        except AttributeError:
+            l_depth = 0
+
+        try:
+            r_depth = self.right_value.depth()
+        except AttributeError:
+            r_depth = 0
+
+        return 1 + max(l_depth, r_depth)
+
     def __str__(self):
         """ Overload str method