Add GPL License
[linpy.git] / pypol / geometry.py
index ce055a4..dffa608 100644 (file)
@@ -1,3 +1,20 @@
+"""
+    This file is part of Linpy.
+
+    Linpy is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Linpy is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with Linpy.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import math
 import numbers
 import operator
@@ -71,6 +88,9 @@ class Coordinates:
 
     __getitem__ = coordinate
 
+    def values(self):
+        yield from self._coordinates.values()
+
     def __bool__(self):
         return any(self._coordinates.values())
 
@@ -104,15 +124,27 @@ class Point(Coordinates, GeometricObject):
     """
 
     def isorigin(self):
+        """
+        Return True if a Point is the origin.
+        """
         return not bool(self)
 
+    def __hash__(self):
+        return super().__hash__()
+
     def __add__(self, other):
+        """
+        Adds a Point to a Vector and returns the result as a Point.
+        """
         if not isinstance(other, Vector):
             return NotImplemented
         coordinates = self._map2(other, operator.add)
         return Point(coordinates)
 
     def __sub__(self, other):
+        """
+        Returns the difference between two Points as a Vector.
+        """
         coordinates = []
         if isinstance(other, Point):
             coordinates = self._map2(other, operator.sub)
@@ -124,10 +156,16 @@ class Point(Coordinates, GeometricObject):
             return NotImplemented
 
     def __eq__(self, other):
+        """
+        Compares two Points for equality.
+        """
         return isinstance(other, Point) and \
             self._coordinates == other._coordinates
 
     def aspolyhedron(self):
+        """
+        Return a Point as a polyhedron.
+        """
         from .polyhedra import Polyhedron
         equalities = []
         for symbol, coordinate in self.coordinates():
@@ -145,15 +183,25 @@ class Vector(Coordinates):
             initial = Point(initial)
         if terminal is None:
             coordinates = initial._coordinates
-        elif not isinstance(terminal, Point):
-            terminal = Point(terminal)
+        else:
+            if not isinstance(terminal, Point):
+                terminal = Point(terminal)
             coordinates = terminal._map2(initial, operator.sub)
         return super().__new__(cls, coordinates)
 
     def isnull(self):
+        """
+        Returns true if a Vector is null.
+        """
         return not bool(self)
 
+    def __hash__(self):
+        return super().__hash__()
+
     def __add__(self, other):
+        """
+        Adds either a Point or Vector to a Vector.
+        """
         if isinstance(other, (Point, Vector)):
             coordinates = self._map2(other, operator.add)
             return other.__class__(coordinates)
@@ -209,6 +257,9 @@ class Vector(Coordinates):
         return result
 
     def __eq__(self, other):
+        """
+        Compares two Vectors for equality.
+        """
         return isinstance(other, Vector) and \
             self._coordinates == other._coordinates
 
@@ -216,6 +267,9 @@ class Vector(Coordinates):
         return hash(tuple(self.coordinates()))
 
     def __mul__(self, other):
+        """
+        Multiplies a Vector by a scalar value.
+        """
         if not isinstance(other, numbers.Real):
             return NotImplemented
         coordinates = self._map(lambda coordinate: other * coordinate)
@@ -224,10 +278,16 @@ class Vector(Coordinates):
     __rmul__ = __mul__
 
     def __neg__(self):
+        """
+        Returns the negated form of a Vector.
+        """
         coordinates = self._map(operator.neg)
         return Vector(coordinates)
 
     def norm(self):
+        """
+        Normalizes a Vector.
+        """
         return math.sqrt(self.norm2())
 
     def norm2(self):
@@ -240,7 +300,12 @@ class Vector(Coordinates):
         return self / self.norm()
 
     def __sub__(self, other):
+        """
+        Subtract a Point or Vector from a Vector.
+        """
         if isinstance(other, (Point, Vector)):
             coordinates = self._map2(other, operator.sub)
             return other.__class__(coordinates)
         return NotImplemented
+        
+# Copyright 2014 MINES ParisTech