update from Atlas

10-seq-hacking/vector_v2.py

@@ -112,6 +112,7 @@ Test of slicing::
 from array import array
 import reprlib
 import math
+import numbers
 
 
 class Vector:
@@ -150,13 +151,13 @@ class Vector:
 
     def __getitem__(self, index):
         cls = type(self)  # <1>
-        if isinstance(index, slice):
-            return cls(self._components[index])  # <2>
-        elif isinstance(index, int):
-            return self._components[index]  # <3>
+        if isinstance(index, slice):  # <2>
+            return cls(self._components[index])  # <3>
+        elif isinstance(index, numbers.Integral):  # <4>
+            return self._components[index]  # <5>
         else:
             msg = '{cls.__name__} indices must be integers'
-            raise TypeError(msg.format(cls=cls))  # <4>
+            raise TypeError(msg.format(cls=cls))  # <6>
 # END VECTOR_V2
 
     @classmethod

10-seq-hacking/vector_v3.py

@@ -155,6 +155,7 @@ Other attributes can be set::
 from array import array
 import reprlib
 import math
+import numbers
 
 
 class Vector:
@@ -194,7 +195,7 @@ class Vector:
         cls = type(self)
         if isinstance(index, slice):
             return cls(self._components[index])
-        elif isinstance(index, int):
+        elif isinstance(index, numbers.Integral):
             return self._components[index]
         else:
             msg = '{.__name__} indices must be integers'

10-seq-hacking/vector_v4.py

@@ -135,17 +135,22 @@ Tests of hashing::
     >>> v2 = Vector([3.1, 4.2])
     >>> v3 = Vector([3, 4, 5])
     >>> v6 = Vector(range(6))
-    >>> hash(v1), hash(v2), hash(v3), hash(v6)
-    (7, 384307168202284039, 2, 1)
-    >>> len(set([v1, v2, v3, v6]))
-    4
+    >>> hash(v1), hash(v3), hash(v6)
+    (7, 2, 1)
 
 
+Most hash values of non-integers vary from a 32-bit to 64-bit CPython build::
+
+    >>> import sys
+    >>> hash(v2) == (384307168202284039 if sys.maxsize > 2**32 else 357915986)
+    True
+
 """
 
 from array import array
 import reprlib
 import math
+import numbers
 import functools
 import operator
 
@@ -192,11 +197,11 @@ class Vector:
         cls = type(self)
         if isinstance(index, slice):
             return cls(self._components[index])
-        elif isinstance(index, int):
+        elif isinstance(index, numbers.Integral):
             return self._components[index]
         else:
-            msg = '{.__name__} indices must be integers'
-            raise TypeError(msg.format(cls))
+            msg = '{cls.__name__} indices must be integers'
+            raise TypeError(msg.format(cls=cls))
 
     shortcut_names = 'xyzt'
 

10-seq-hacking/vector_v5.py

@@ -136,10 +136,15 @@ Tests of hashing::
     >>> v2 = Vector([3.1, 4.2])
     >>> v3 = Vector([3, 4, 5])
     >>> v6 = Vector(range(6))
-    >>> hash(v1), hash(v2), hash(v3), hash(v6)
-    (7, 384307168202284039, 2, 1)
-    >>> len(set([v1, v2, v3, v6]))
-    4
+    >>> hash(v1), hash(v3), hash(v6)
+    (7, 2, 1)
+
+
+Most hash values of non-integers vary from a 32-bit to 64-bit CPython build::
+
+    >>> import sys
+    >>> hash(v2) == (384307168202284039 if sys.maxsize > 2**32 else 357915986)
+    True
 
 
 Tests of ``format()`` with Cartesian coordinates in 2D::
@@ -187,6 +192,7 @@ Tests of ``format()`` with spherical coordinates in 2D, 3D and 4D::
 from array import array
 import reprlib
 import math
+import numbers
 import functools
 import operator
 import itertools  # <1>
@@ -234,7 +240,7 @@ class Vector:
         cls = type(self)
         if isinstance(index, slice):
             return cls(self._components[index])
-        elif isinstance(index, int):
+        elif isinstance(index, numbers.Integral):
             return self._components[index]
         else:
             msg = '{.__name__} indices must be integers'

11-iface-abc/tombola_tests.rst

@@ -50,7 +50,7 @@ thrown when the device is empty::
     OK
 
 
-Load and pick 100 balls to verify that they are all come out::
+Load and pick 100 balls to verify that they all come out::
 
     >>> balls = list(range(100))
     >>> globe = ConcreteTombola(balls)
@@ -63,7 +63,7 @@ Load and pick 100 balls to verify that they are all come out::
     True
 
 
-Check that the order has changed is not simply reversed either::
+Check that the order has changed and is not simply reversed::
 
     >>> picks != balls
     True
@@ -71,9 +71,9 @@ Check that the order has changed is not simply reversed either::
     True
 
 Note: the previous 2 tests have a *very* small chance of failing
-even if the implementation is OK. The probability of the 100 
+even if the implementation is OK. The probability of the 100
 balls coming out, by chance, in the order they were loaded is
-1/100!, or approximately 1.07e-158. It's much easier to win the 
+1/100!, or approximately 1.07e-158. It's much easier to win the
 Lotto or to become a billionaire working as a programmer.
 
 THE END

11-iface-abc/tombolist.py

@@ -8,7 +8,7 @@ class TomboList(list):  # <2>
     def pick(self):
         if self:  # <3>
             position = randrange(len(self))
-            return super().pop(position)  # <4>
+            return self.pop(position)  # <4>
         else:
             raise LookupError('pop from empty TomboList')
 

12-inheritance/diamond.py

@@ -14,6 +14,14 @@ class C(A):
 
 
 class D(B, C):
-    def pingpong(self):
+
+    def ping(self):
         super().ping()
+        print('post-ping:', self)
+
+    def pingpong(self):
+        self.ping()
+        super().ping()
+        self.pong()
         super().pong()
+        C.pong(self)

13-op-overloading/unary_plus_decimal.py

@@ -0,0 +1,35 @@
+"""
+# BEGIN UNARY_PLUS_DECIMAL
+
+>>> import decimal
+>>> ctx = decimal.getcontext()  # <1>
+>>> ctx.prec = 40  # <2>
+>>> one_third = decimal.Decimal('1') / decimal.Decimal('3')  # <3>
+>>> one_third  # <4>
+Decimal('0.3333333333333333333333333333333333333333')
+>>> one_third == +one_third  # <5>
+True
+>>> ctx.prec = 28  # <6>
+>>> one_third == +one_third  # <7>
+False
+>>> +one_third  # <8>
+Decimal('0.3333333333333333333333333333')
+
+# END UNARY_PLUS_DECIMAL
+
+"""
+
+import decimal
+
+if __name__ == '__main__':
+
+    with decimal.localcontext() as ctx:
+        ctx.prec = 40
+        print('precision:', ctx.prec)
+        one_third = decimal.Decimal('1') / decimal.Decimal('3')
+        print('    one_third:', one_third)
+        print('   +one_third:', +one_third)
+
+    print('precision:', decimal.getcontext().prec)
+    print('    one_third:', one_third)
+    print('   +one_third:', +one_third)

13-op-overloading/vector2d_v3.py

@@ -0,0 +1,151 @@
+"""
+A 2-dimensional vector class
+
+    >>> v1 = Vector2d(3, 4)
+    >>> print(v1.x, v1.y)
+    3.0 4.0
+    >>> x, y = v1
+    >>> x, y
+    (3.0, 4.0)
+    >>> v1
+    Vector2d(3.0, 4.0)
+    >>> v1_clone = eval(repr(v1))
+    >>> v1 == v1_clone
+    True
+    >>> print(v1)
+    (3.0, 4.0)
+    >>> octets = bytes(v1)
+    >>> octets
+    b'd\\x00\\x00\\x00\\x00\\x00\\x00\\x08@\\x00\\x00\\x00\\x00\\x00\\x00\\x10@'
+    >>> abs(v1)
+    5.0
+    >>> bool(v1), bool(Vector2d(0, 0))
+    (True, False)
+
+
+Test of ``.frombytes()`` class method:
+
+    >>> v1_clone = Vector2d.frombytes(bytes(v1))
+    >>> v1_clone
+    Vector2d(3.0, 4.0)
+    >>> v1 == v1_clone
+    True
+
+
+Tests of ``format()`` with Cartesian coordinates:
+
+    >>> format(v1)
+    '(3.0, 4.0)'
+    >>> format(v1, '.2f')
+    '(3.00, 4.00)'
+    >>> format(v1, '.3e')
+    '(3.000e+00, 4.000e+00)'
+
+
+Tests of the ``angle`` method::
+
+    >>> Vector2d(0, 0).angle()
+    0.0
+    >>> Vector2d(1, 0).angle()
+    0.0
+    >>> epsilon = 10**-8
+    >>> abs(Vector2d(0, 1).angle() - math.pi/2) < epsilon
+    True
+    >>> abs(Vector2d(1, 1).angle() - math.pi/4) < epsilon
+    True
+
+
+Tests of ``format()`` with polar coordinates:
+
+    >>> format(Vector2d(1, 1), 'p')  # doctest:+ELLIPSIS
+    '<1.414213..., 0.785398...>'
+    >>> format(Vector2d(1, 1), '.3ep')
+    '<1.414e+00, 7.854e-01>'
+    >>> format(Vector2d(1, 1), '0.5fp')
+    '<1.41421, 0.78540>'
+
+
+Tests of `x` and `y` read-only properties:
+
+    >>> v1.x, v1.y
+    (3.0, 4.0)
+    >>> v1.x = 123
+    Traceback (most recent call last):
+      ...
+    AttributeError: can't set attribute
+
+
+Tests of hashing:
+
+    >>> v1 = Vector2d(3, 4)
+    >>> v2 = Vector2d(3.1, 4.2)
+    >>> hash(v1), hash(v2)
+    (7, 384307168202284039)
+    >>> len(set([v1, v2]))
+    2
+
+"""
+
+from array import array
+import math
+
+class Vector2d:
+    typecode = 'd'
+
+    def __init__(self, x, y):
+        self.__x = float(x)
+        self.__y = float(y)
+
+    @property
+    def x(self):
+        return self.__x
+
+    @property
+    def y(self):
+        return self.__y
+
+    def __iter__(self):
+        return (i for i in (self.x, self.y))
+
+    def __repr__(self):
+        class_name = type(self).__name__
+        return '{}({!r}, {!r})'.format(class_name, *self)
+
+    def __str__(self):
+        return str(tuple(self))
+
+    def __bytes__(self):
+        return (bytes([ord(self.typecode)]) +
+                bytes(array(self.typecode, self)))
+
+    def __eq__(self, other):
+        return tuple(self) == tuple(other)
+
+    def __hash__(self):
+        return hash(self.x) ^ hash(self.y)
+
+    def __abs__(self):
+        return math.hypot(self.x, self.y)
+
+    def __bool__(self):
+        return bool(abs(self))
+
+    def angle(self):
+        return math.atan2(self.y, self.x)
+
+    def __format__(self, fmt_spec=''):
+        if fmt_spec.endswith('p'):
+            fmt_spec = fmt_spec[:-1]
+            coords = (abs(self), self.angle())
+            outer_fmt = '<{}, {}>'
+        else:
+            coords = self
+            outer_fmt = '({}, {})'
+        components = (format(c, fmt_spec) for c in coords)
+        return outer_fmt.format(*components)
+
+    @classmethod
+    def frombytes(cls, octets):
+        typecode = chr(octets[0])
+        memv = memoryview(octets[1:]).cast(typecode)
+        return cls(*memv)

13-op-overloading/vector_py3_5.py

@@ -137,10 +137,15 @@ Tests of hashing::
     >>> v2 = Vector([3.1, 4.2])
     >>> v3 = Vector([3, 4, 5])
     >>> v6 = Vector(range(6))
-    >>> hash(v1), hash(v2), hash(v3), hash(v6)
-    (7, 384307168202284039, 2, 1)
-    >>> len(set([v1, v2, v3, v6]))
-    4
+    >>> hash(v1), hash(v3), hash(v6)
+    (7, 2, 1)
+
+
+Most hash values of non-integers vary from a 32-bit to 64-bit Python build::
+
+    >>> import sys
+    >>> hash(v2) == (384307168202284039 if sys.maxsize > 2**32 else 357915986)
+    True
 
 
 Tests of ``format()`` with Cartesian coordinates in 2D::

13-op-overloading/vector_v6.py

@@ -135,10 +135,15 @@ Tests of hashing::
     >>> v2 = Vector([3.1, 4.2])
     >>> v3 = Vector([3, 4, 5])
     >>> v6 = Vector(range(6))
-    >>> hash(v1), hash(v2), hash(v3), hash(v6)
-    (7, 384307168202284039, 2, 1)
-    >>> len(set([v1, v2, v3, v6]))
-    4
+    >>> hash(v1), hash(v3), hash(v6)
+    (7, 2, 1)
+
+
+Most hash values of non-integers vary from a 32-bit to 64-bit Python build::
+
+    >>> import sys
+    >>> hash(v2) == (384307168202284039 if sys.maxsize > 2**32 else 357915986)
+    True
 
 
 Tests of ``format()`` with Cartesian coordinates in 2D::
@@ -183,6 +188,17 @@ Tests of ``format()`` with spherical coordinates in 2D, 3D and 4D::
     '<1.00000, 1.57080, 0.00000, 0.00000>'
 
 
+Unary operator tests::
+
+    >>> v1 = Vector([3, 4])
+    >>> abs(v1)
+    5.0
+    >>> -v1
+    Vector([-3.0, -4.0])
+    >>> +v1
+    Vector([3.0, 4.0])
+
+
 Basic tests of operator ``+``::
 
     >>> v1 = Vector([3, 4, 5])
@@ -231,6 +247,7 @@ Tests of ``+`` with an unsuitable operand:
 from array import array
 import reprlib
 import math
+import numbers
 import functools
 import operator
 import itertools
@@ -265,9 +282,17 @@ class Vector:
         hashes = (hash(x) for x in self)
         return functools.reduce(operator.xor, hashes, 0)
 
+# BEGIN VECTOR_V6_UNARY
     def __abs__(self):
         return math.sqrt(sum(x * x for x in self))
 
+    def __neg__(self):
+        return Vector(-x for x in self)  # <1>
+
+    def __pos__(self):
+        return Vector(self)  # <2>
+# END VECTOR_V6_UNARY
+
     def __bool__(self):
         return bool(abs(self))
 
@@ -278,7 +303,7 @@ class Vector:
         cls = type(self)
         if isinstance(index, slice):
             return cls(self._components[index])
-        elif isinstance(index, int):
+        elif isinstance(index, numbers.Integral):
             return self._components[index]
         else:
             msg = '{.__name__} indices must be integers'
@@ -324,7 +349,7 @@ class Vector:
         memv = memoryview(octets[1:]).cast(typecode)
         return cls(memv)
 
-# BEGIN VECTOR_V6
+# BEGIN VECTOR_V6_ADD
     def __add__(self, other):
         try:
             pairs = itertools.zip_longest(self, other, fillvalue=0.0)
@@ -334,4 +359,4 @@ class Vector:
 
     def __radd__(self, other):
         return self + other
-# END VECTOR_V6
+# END VECTOR_V6_ADD

13-op-overloading/vector_v7.py

@@ -135,10 +135,15 @@ Tests of hashing::
     >>> v2 = Vector([3.1, 4.2])
     >>> v3 = Vector([3, 4, 5])
     >>> v6 = Vector(range(6))
-    >>> hash(v1), hash(v2), hash(v3), hash(v6)
-    (7, 384307168202284039, 2, 1)
-    >>> len(set([v1, v2, v3, v6]))
-    4
+    >>> hash(v1), hash(v3), hash(v6)
+    (7, 2, 1)
+
+
+Most hash values of non-integers vary from a 32-bit to 64-bit Python build::
+
+    >>> import sys
+    >>> hash(v2) == (384307168202284039 if sys.maxsize > 2**32 else 357915986)
+    True
 
 
 Tests of ``format()`` with Cartesian coordinates in 2D::
@@ -183,6 +188,17 @@ Tests of ``format()`` with spherical coordinates in 2D, 3D and 4D::
     '<1.00000, 1.57080, 0.00000, 0.00000>'
 
 
+Unary operator tests::
+
+    >>> v1 = Vector([3, 4])
+    >>> abs(v1)
+    5.0
+    >>> -v1
+    Vector([-3.0, -4.0])
+    >>> +v1
+    Vector([3.0, 4.0])
+
+
 Basic tests of operator ``+``::
 
     >>> v1 = Vector([3, 4, 5])
@@ -258,10 +274,10 @@ Tests of ``*`` with unsuitable operands::
 from array import array
 import reprlib
 import math
+import numbers
 import functools
 import operator
 import itertools
-import numbers
 
 
 class Vector:
@@ -296,6 +312,12 @@ class Vector:
     def __abs__(self):
         return math.sqrt(sum(x * x for x in self))
 
+    def __neg__(self):
+        return Vector(-x for x in self)
+
+    def __pos__(self):
+        return Vector(self)
+
     def __bool__(self):
         return bool(abs(self))
 
@@ -306,7 +328,7 @@ class Vector:
         cls = type(self)
         if isinstance(index, slice):
             return cls(self._components[index])
-        elif isinstance(index, int):
+        elif isinstance(index, numbers.Integral):
             return self._components[index]
         else:
             msg = '{.__name__} indices must be integers'

13-op-overloading/vector_v8.py

@@ -135,10 +135,15 @@ Tests of hashing::
     >>> v2 = Vector([3.1, 4.2])
     >>> v3 = Vector([3, 4, 5])
     >>> v6 = Vector(range(6))
-    >>> hash(v1), hash(v2), hash(v3), hash(v6)
-    (7, 384307168202284039, 2, 1)
-    >>> len(set([v1, v2, v3, v6]))
-    4
+    >>> hash(v1), hash(v3), hash(v6)
+    (7, 2, 1)
+
+
+Most hash values of non-integers vary from a 32-bit to 64-bit Python build::
+
+    >>> import sys
+    >>> hash(v2) == (384307168202284039 if sys.maxsize > 2**32 else 357915986)
+    True
 
 
 Tests of ``format()`` with Cartesian coordinates in 2D::
@@ -183,6 +188,17 @@ Tests of ``format()`` with spherical coordinates in 2D, 3D and 4D::
     '<1.00000, 1.57080, 0.00000, 0.00000>'
 
 
+Unary operator tests::
+
+    >>> v1 = Vector([3, 4])
+    >>> abs(v1)
+    5.0
+    >>> -v1
+    Vector([-3.0, -4.0])
+    >>> +v1
+    Vector([3.0, 4.0])
+
+
 Basic tests of operator ``+``::
 
     >>> v1 = Vector([3, 4, 5])
@@ -283,10 +299,10 @@ Tests of operator `!=`::
 from array import array
 import reprlib
 import math
+import numbers
 import functools
 import operator
 import itertools
-import numbers
 
 
 class Vector:
@@ -326,6 +342,12 @@ class Vector:
     def __abs__(self):
         return math.sqrt(sum(x * x for x in self))
 
+    def __neg__(self):
+        return Vector(-x for x in self)
+
+    def __pos__(self):
+        return Vector(self)
+
     def __bool__(self):
         return bool(abs(self))
 
@@ -336,7 +358,7 @@ class Vector:
         cls = type(self)
         if isinstance(index, slice):
             return cls(self._components[index])
-        elif isinstance(index, int):
+        elif isinstance(index, numbers.Integral):
             return self._components[index]
         else:
             msg = '{.__name__} indices must be integers'

concurrency/parallel/lelo_ex.py

@@ -0,0 +1,24 @@
+import os
+from time import sleep, time
+
+from lelo import parallel
+
+DELAY = .2
+
+@parallel
+def loiter(serial, delay):
+    pid = os.getpid()
+    print('%2d pid = %d' % (serial, pid))
+    sleep(delay)
+    return pid
+
+t0 = time()
+
+results = []
+for i in range(15):
+    res = loiter(i, DELAY)
+    results.append(res)
+
+print('Processes used: ', list(set(results)))
+
+print('### Elapsed time: %0.2f' % (time() - t0))

concurrency/parallel/llize.py

@@ -0,0 +1,19 @@
+import os
+from parallelize import parallelize
+from time import sleep, time
+
+print('one process:')
+t0 = time()
+for i in range(12):
+    print('%2d pid = %d' % (i, os.getpid()))
+    sleep(.2)
+print('elapsed time: %0.2f' % (time() - t0))
+
+print()
+
+print('several processes:')
+t0 = time()
+for i in parallelize(range(12)):
+    print('%2d pid = %d' % (i, os.getpid()))
+    sleep(.2)
+print('elapsed time: %0.2f' % (time() - t0))

concurrency/parallel/llize_ex.py

@@ -0,0 +1,23 @@
+import os
+from time import sleep, time
+
+from parallelize import parallelize, per_item
+
+DELAY = .2
+
+def loiter(serial, delay):
+    pid = os.getpid()
+    print('%2d pid = %d' % (serial, pid))
+    sleep(delay)
+    return pid
+
+t0 = time()
+
+results = []
+for i in parallelize(range(15), fork=per_item):
+    res = loiter(i, DELAY)
+    results.append(res)
+
+print('Processes used: ', list(set(results)))
+
+print('### Elapsed time: %0.2f' % (time() - t0))