update

classes/multivector_v1_hash.py

@@ -0,0 +1,123 @@
+"""
+A multi-dimensional ``MultiVector`` class, take 1
+
+Tests with 2-dimensions (same results as ``vector_v1.py``)::
+
+    >>> v1 = MultiVector([3, 4])
+    >>> x, y = v1
+    >>> x, y
+    (3.0, 4.0)
+    >>> v1
+    MultiVector([3.0, 4.0])
+    >>> v1_clone = eval(repr(v1))
+    >>> v1 == v1_clone
+    True
+    >>> print(v1)
+    (3.0, 4.0)
+    >>> octets = bytes(v1)
+    >>> octets
+    b'\\x00\\x00\\x00\\x00\\x00\\x00\\x08@\\x00\\x00\\x00\\x00\\x00\\x00\\x10@'
+    >>> abs(v1)
+    5.0
+    >>> bool(v1), bool(MultiVector([0, 0]))
+    (True, False)
+
+Test of ``.frombytes()`` class method:
+
+    >>> v1_clone = MultiVector.frombytes(bytes(v1))
+    >>> v1_clone
+    MultiVector([3.0, 4.0])
+    >>> v1 == v1_clone
+    True
+
+Tests with 3-dimensions::
+
+    >>> v1 = MultiVector([3, 4, 5])
+    >>> x, y, z = v1
+    >>> x, y, z
+    (3.0, 4.0, 5.0)
+    >>> v1
+    MultiVector([3.0, 4.0, 5.0])
+    >>> v1_clone = eval(repr(v1))
+    >>> v1 == v1_clone
+    True
+    >>> print(v1)
+    (3.0, 4.0, 5.0)
+    >>> abs(v1)  # doctest:+ELLIPSIS
+    7.071067811...
+    >>> bool(v1), bool(MultiVector([0, 0, 0]))
+    (True, False)
+
+Tests with many dimensions::
+
+    >>> v7 = MultiVector(range(7))
+    >>> v7
+    MultiVector([0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0])
+    >>> abs(v7)  # doctest:+ELLIPSIS
+    9.53939201...
+
+Test of ``.__bytes__`` and ``.frombytes()`` methods::
+
+    >>> v1 = MultiVector([3, 4, 5])
+    >>> v1_clone = MultiVector.frombytes(bytes(v1))
+    >>> v1_clone
+    MultiVector([3.0, 4.0, 5.0])
+    >>> v1 == v1_clone
+    True
+
+Tests of hashing::
+
+    >>> v1 = MultiVector([3, 4])
+    >>> v2 = MultiVector([3.1, 4.2])
+    >>> v3 = MultiVector([3, 4, 5])
+    >>> v4 = MultiVector(range(10))
+    >>> hash(v1), hash(v2), hash(v3), hash(v4)
+    (7, 384307168202284039, 2, 1)
+    >>> len(set([v1, v2, v3, v4]))
+    4
+
+
+"""
+
+from array import array
+import math
+import functools
+import operator
+
+
+class MultiVector:
+    typecode = 'd'
+
+    def __init__(self, components):
+        self._components = array(MultiVector.typecode, components)
+
+    def __iter__(self):
+        return iter(self._components)
+
+    def __repr__(self):
+        components = ', '.join(repr(x) for x in self)
+        return 'MultiVector([{}])'.format(components)
+
+    def __str__(self):
+        return str(tuple(self))
+
+    def __bytes__(self):
+        return bytes(self._components)
+
+    def __eq__(self, other):
+        return tuple(self) == tuple(other)
+
+    def __hash__(self):
+        hashes = (hash(x) for x in self)
+        return functools.reduce(operator.xor, hashes)
+
+    def __abs__(self):
+        return math.sqrt(sum(x * x for x in self))
+
+    def __bool__(self):
+        return bool(abs(self))
+
+    @classmethod
+    def frombytes(cls, octets):
+        memv = memoryview(octets).cast(cls.typecode)
+        return cls(memv)