import numbers
import operator
-from collections import OrderedDict
+from collections import OrderedDict, Mapping
from .linexprs import Symbol
]
-def _map(obj, func):
- for symbol, coordinate in obj.coordinates():
- yield symbol, func(coordinate)
+class Coordinates:
-def _iter2(obj1, obj2):
- if obj1.symbols != obj2.symbols:
- raise ValueError('arguments must belong to the same space')
- coordinates1 = obj1._coordinates.values()
- coordinates2 = obj2._coordinates.values()
- yield from zip(obj1.symbols, coordinates1, coordinates2)
-
-def _map2(obj1, obj2, func):
- for symbol, coordinate1, coordinate2 in _iter2(obj1, obj2):
- yield symbol, func(coordinate1, coordinate2)
-
-
-class Point:
- """
- This class represents points in space.
- """
+ __slots__ = (
+ '_coordinates',
+ )
- def __new__(cls, coordinates=None):
- if isinstance(coordinates, dict):
+ def __new__(cls, coordinates):
+ if isinstance(coordinates, Mapping):
coordinates = coordinates.items()
self = object().__new__(cls)
self._coordinates = OrderedDict()
__getitem__ = coordinate
- def isorigin(self):
- return not bool(self)
-
def __bool__(self):
return any(self._coordinates.values())
+ def __hash__(self):
+ return hash(tuple(self.coordinates()))
+
+ def __repr__(self):
+ string = ', '.join(['{!r}: {!r}'.format(symbol, coordinate)
+ for symbol, coordinate in self.coordinates()])
+ return '{}({{{}}})'.format(self.__class__.__name__, string)
+
+ def _map(self, func):
+ for symbol, coordinate in self.coordinates():
+ yield symbol, func(coordinate)
+
+ def _iter2(self, other):
+ if self.symbols != other.symbols:
+ raise ValueError('arguments must belong to the same space')
+ coordinates1 = self._coordinates.values()
+ coordinates2 = other._coordinates.values()
+ yield from zip(self.symbols, coordinates1, coordinates2)
+
+ def _map2(self, other, func):
+ for symbol, coordinate1, coordinate2 in self._iter2(other):
+ yield symbol, func(coordinate1, coordinate2)
+
+
+class Point(Coordinates):
+ """
+ This class represents points in space.
+ """
+
+ def isorigin(self):
+ return not bool(self)
+
def __add__(self, other):
if not isinstance(other, Vector):
return NotImplemented
- coordinates = _map2(self, other, operator.add)
+ coordinates = self._map2(other, operator.add)
return Point(coordinates)
def __sub__(self, other):
coordinates = []
if isinstance(other, Point):
- coordinates = _map2(self, other, operator.sub)
+ coordinates = self._map2(other, operator.sub)
return Vector(coordinates)
elif isinstance(other, Vector):
- coordinates = _map2(self, other, operator.sub)
+ coordinates = self._map2(other, operator.sub)
return Point(coordinates)
else:
return NotImplemented
return isinstance(other, Point) and \
self._coordinates == other._coordinates
- def __hash__(self):
- return hash(tuple(self.coordinates()))
-
- def __repr__(self):
- string = ', '.join(['{!r}: {!r}'.format(symbol, coordinate)
- for symbol, coordinate in self.coordinates()])
- return '{}({{{}}})'.format(self.__class__.__name__, string)
+ def aspolyhedron(self):
+ from .polyhedra import Polyhedron
+ equalities = []
+ for symbol, coordinate in self.coordinates():
+ equalities.append(symbol - coordinate)
+ return Polyhedron(equalities)
-class Vector:
+class Vector(Coordinates):
"""
This class represents displacements in space.
"""
- __slots__ = (
- '_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 = _map2(terminal, 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 = _map2(self, other, operator.add)
+ coordinates = self._map2(other, operator.add)
return other.__class__(coordinates)
return NotImplemented
"""
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):
"""
if not isinstance(other, numbers.Real):
return NotImplemented
- coordinates = _map(self, lambda coordinate: coordinate / other)
+ coordinates = self._map(lambda coordinate: coordinate / other)
return Vector(coordinates)
def dot(self, other):
if not isinstance(other, Vector):
raise TypeError('argument must be a Vector instance')
result = 0
- for symbol, coordinate1, coordinate2 in _iter2(self, other):
+ for symbol, coordinate1, coordinate2 in self._iter2(other):
result += coordinate1 * coordinate2
return result
def __mul__(self, other):
if not isinstance(other, numbers.Real):
return NotImplemented
- coordinates = _map(self, lambda coordinate: other * coordinate)
+ coordinates = self._map(lambda coordinate: other * coordinate)
return Vector(coordinates)
__rmul__ = __mul__
def __neg__(self):
- coordinates = _map(self, operator.neg)
+ coordinates = self._map(operator.neg)
return Vector(coordinates)
def norm(self):
def __sub__(self, other):
if isinstance(other, (Point, Vector)):
- coordinates = _map2(self, other, operator.sub)
+ 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)
projects / linpy.git / blobdiff