Add warning in widening documentation

[linpy.git] / doc / reference.rst

diff --git a/doc/reference.rst b/doc/reference.rst
index e0efdde..18e69c0 100644 (file)
--- a/doc/reference.rst
+++ b/doc/reference.rst
@@ -203,7 +203,7 @@ For example, if ``x`` is a :class:`Symbol`, then ``x + 1`` is an instance of :cl
     .. classmethod:: fromsympy(expr)
 
         Create a linear expression from a :mod:`sympy` expression.
-        Raise :exc:`ValueError` is the :mod:`sympy` expression is not linear.
+        Raise :exc:`TypeError` is the :mod:`sympy` expression is not linear.
 
     .. method:: tosympy()
 
@@ -282,6 +282,8 @@ This space can be unbounded.
 
         Compute the *standard widening* of two polyhedra, à la Halbwachs.
 
+        In its current implementation, this method is slow and should not be used on large polyhedra.
+
 
 .. data:: Empty
 
@@ -677,7 +679,7 @@ Geometric Objects
     .. method:: cross(vector)
 
         Compute the cross product of two 3D vectors.
-        If either one of the vectors is not tridimensional, a :exc:`ValueError` exception is raised.
+        If either one of the vectors is not three-dimensional, a :exc:`ValueError` exception is raised.
 
     .. method:: dot(vector)