Make Coordinate instantiable

[linpy.git] / pypol / coordinates.py

diff --git a/pypol/coordinates.py b/pypol/coordinates.py
index eb8e78c..a880178 100644 (file)
--- a/pypol/coordinates.py
+++ b/pypol/coordinates.py
@@ -2,8 +2,7 @@ import math
 import numbers
 import operator
 
-from abc import ABC, abstractmethod
-from collections import OrderedDict
+from collections import OrderedDict, Mapping
 
 from .linexprs import Symbol
 
@@ -14,15 +13,25 @@ __all__ = [
 ]
 
 
-class Coordinates(ABC):
+class Coordinates:
 
     __slots__ = (
         '_coordinates',
     )
 
-    @abstractmethod
-    def __new__(cls):
-        super().__new__(cls)
+    def __new__(cls, coordinates):
+        if isinstance(coordinates, Mapping):
+            coordinates = coordinates.items()
+        self = object().__new__(cls)
+        self._coordinates = OrderedDict()
+        for symbol, coordinate in sorted(coordinates,
+                key=lambda item: item[0].sortkey()):
+            if not isinstance(symbol, Symbol):
+                raise TypeError('symbols must be Symbol instances')
+            if not isinstance(coordinate, numbers.Real):
+                raise TypeError('coordinates must be real numbers')
+            self._coordinates[symbol] = coordinate
+        return self
 
     @property
     def symbols(self):
@@ -74,20 +83,6 @@ class Point(Coordinates):
     This class represents points in space.
     """
 
-    def __new__(cls, coordinates=None):
-        if isinstance(coordinates, dict):
-            coordinates = coordinates.items()
-        self = object().__new__(cls)
-        self._coordinates = OrderedDict()
-        for symbol, coordinate in sorted(coordinates,
-                key=lambda item: item[0].sortkey()):
-            if not isinstance(symbol, Symbol):
-                raise TypeError('symbols must be Symbol instances')
-            if not isinstance(coordinate, numbers.Real):
-                raise TypeError('coordinates must be real numbers')
-            self._coordinates[symbol] = coordinate
-        return self
-
     def isorigin(self):
         return not bool(self)
 
@@ -112,6 +107,13 @@ class Point(Coordinates):
         return isinstance(other, Point) and \
             self._coordinates == other._coordinates
 
+    def aspolyhedron(self):
+        from .polyhedra import Polyhedron
+        equalities = []
+        for symbol, coordinate in self.coordinates():
+            equalities.append(symbol - coordinate)
+        return Polyhedron(equalities)
+
 
 class Vector(Coordinates):
     """
@@ -123,40 +125,18 @@ class Vector(Coordinates):
     )
 
     def __new__(cls, initial, terminal=None):
-        self = object().__new__(cls)
         if not isinstance(initial, Point):
             initial = Point(initial)
         if terminal is None:
-            self._coordinates = initial._coordinates
+            coordinates = initial._coordinates
         elif not isinstance(terminal, Point):
             terminal = Point(terminal)
-            self._coordinates = terminal._map2(initial, operator.sub)
-        return self
-
-    @property
-    def symbols(self):
-        return tuple(self._coordinates)
-
-    @property
-    def dimension(self):
-        return len(self.symbols)
-
-    def coordinates(self):
-        yield from self._coordinates.items()
-
-    def coordinate(self, symbol):
-        if not isinstance(symbol, Symbol):
-            raise TypeError('symbol must be a Symbol instance')
-        return self._coordinates[symbol]
-
-    __getitem__ = coordinate
+            coordinates = terminal._map2(initial, operator.sub)
+        return super().__new__(cls, coordinates)
 
     def isnull(self):
         return not bool(self)
 
-    def __bool__(self):
-        return any(self._coordinates.values())
-
     def __add__(self, other):
         if isinstance(other, (Point, Vector)):
             coordinates = self._map2(other, operator.add)
@@ -171,7 +151,7 @@ class Vector(Coordinates):
         """
         if not isinstance(other, Vector):
             raise TypeError('argument must be a Vector instance')
-        cosinus = self.dot(other) / (self.norm() * other.norm())
+        cosinus = self.dot(other) / (self.norm()*other.norm())
         return math.acos(cosinus)
 
     def cross(self, other):
@@ -248,8 +228,3 @@ class Vector(Coordinates):
             coordinates = self._map2(other, operator.sub)
             return other.__class__(coordinates)
         return NotImplemented
-
-    def __repr__(self):
-        string = ', '.join(['{!r}: {!r}'.format(symbol, coordinate)
-            for symbol, coordinate in self.coordinates()])
-        return '{}({{{}}})'.format(self.__class__.__name__, string)