finished up session 08

Author: PythonCHB

Examples/Session08/iterator_1.py

@@ -0,0 +1,32 @@
+#!/usr/bin/env python
+
+"""
+Simple iterator examples
+"""
+
+
+class IterateMe_1(object):
+    """
+    About as simple an iterator as you can get:
+
+    returns the sequence of numbers from zero to 4
+    ( like xrange(4) )
+    """
+    def __init__(self, stop=5):
+        self.current = -1
+        self.stop = stop
+    def __iter__(self):
+        return self
+    def next(self):
+        self.current += 1
+        if self.current < self.stop:
+            return self.current
+        else:
+            raise StopIteration
+
+if __name__ == "__main__":
+
+    print "Testing the iterator"
+    for i in IterateMe_1():
+        print i
+

Examples/Session08/my_for.py

@@ -0,0 +1,50 @@
+#!/usr/bin/env python
+
+"""
+hand writing 'for'
+
+demonstrates how for interacts with an iterable
+"""
+
+
+l = [1,2,3,4,5,]
+
+
+def my_for(an_iterable, func):
+    """
+    Emulation of a for loop.
+
+    func() will be called with each item in an_iterable
+
+    :param an_iterable: anything that satisfies the interation protocol
+
+    :param func: a callable -- it will be called, passing in each item
+                 in an_iterable.
+
+    """
+    # equiv of "for i in l:"
+    iterator = iter(an_iterable)
+    while True:
+        try:
+            i = iterator.next()
+        except StopIteration:
+            break
+        func(i)
+
+
+if __name__ == "__main__":
+
+    def print_func(x):
+        print x
+
+    l = [1,2,3,4,5,]
+    my_for(l, print_func)
+
+    t = ('a','b','c','d')
+
+    my_for(t, print_func)
+
+
+
+
+

Examples/Session08/test_generator.py

@@ -0,0 +1,78 @@
+"""
+test_generator.py
+
+tests the solution to the generator lab
+
+can be run with py.test or nosetests
+"""
+
+import generator_solution as gen
+
+
+def test_intsum():
+
+    g = gen.intsum()
+
+    assert g.next() == 0
+    assert g.next() == 1
+    assert g.next() == 3
+    assert g.next() == 6
+    assert g.next() == 10
+    assert g.next() == 15
+
+
+def test_intsum2():
+
+    g = gen.intsum2()
+
+    assert g.next() == 0
+    assert g.next() == 1
+    assert g.next() == 3
+    assert g.next() == 6
+    assert g.next() == 10
+    assert g.next() == 15
+
+
+def test_doubler():
+
+    g = gen.doubler()
+
+    assert g.next() == 1
+    assert g.next() == 2
+    assert g.next() == 4
+    assert g.next() == 8
+    assert g.next() == 16
+    assert g.next() == 32
+
+    for i in range(10):
+        j = g.next()
+
+    assert j == 2**15
+
+
+def test_fib():
+    g = gen.fib()
+
+    assert g.next() == 1
+    assert g.next() == 1
+    assert g.next() == 2
+    assert g.next() == 3
+    assert g.next() == 5
+    assert g.next() == 8
+    assert g.next() == 13
+    assert g.next() == 21
+
+
+def test_prime():
+    g = gen.prime()
+
+    assert g.next() == 2
+    assert g.next() == 3
+    assert g.next() == 5
+    assert g.next() == 7
+    assert g.next() == 11
+    assert g.next() == 13
+    assert g.next() == 17
+    assert g.next() == 19
+    assert g.next() == 23
+

Examples/Session08/yield_example.py

@@ -0,0 +1,22 @@
+def counter():
+    print 'counter: starting counter'
+    i = -3
+    while i < 3:
+        i = i + 1
+        print 'counter: yield', i
+        yield i
+
+
+
+if __name__ == '__main__':
+    print "the generator function:"
+    print repr(counter)
+    print "call generator function"
+
+    c = counter()
+    print "the generator:"
+    print repr(c)
+
+    print 'iterate'
+    for item in c:
+        print 'received:', item

Solutions/Session08/sparse_array.py

@@ -20,7 +20,7 @@ def __len__(self):
         return self.length
 
     def __getitem__(self, key):
-        try: 
+        try:
             return self.sparse_array[key]
         except KeyError:
             if key >= self.length:
@@ -33,17 +33,17 @@ def __setitem__(self, key, value):
         if value != 0:
             self.sparse_array[key] = value
         else:
-            # if the value is being set to zero, we probably need to 
+            # if the value is being set to zero, we probably need to
             # remove a key from our dictionary.
             self.sparse_array.pop(key, None)
 
     def __delitem__(self, key):
-        # we probably need to move the keys if we are not deleting the last 
+        # we probably need to move the keys if we are not deleting the last
         # number, use pop in case it was a zero
         if key == self.length - 1:
             self.sparse_array.pop(key, None)
         else:
-            # since we need to adjust all of the keys after the one we are 
+            # since we need to adjust all of the keys after the one we are
             # deleting, probably most efficient to create a new dictionary
             new_dict = {}
             for k, v in self.sparse_array.iteritems():

Solutions/Session08/test_sparse_array.py

@@ -70,7 +70,7 @@ def test_delete_last_number():
     my_array, my_sparse = set_up()
     del(my_sparse[13])
     # should get an error?
-    print 'print some stuf damnit'
+    print 'print some stuff damnit'
     with pytest.raises(IndexError):
         my_sparse[13]
     assert len(my_sparse) == 13

slides_sources/source/conf.py

@@ -35,6 +35,7 @@
     'sphinx.ext.todo',
     'sphinx.ext.coverage',
     'sphinx.ext.pngmath',
+    # 'sphinx.ext.mathjax',
     'sphinx.ext.ifconfig',
     'IPython.sphinxext.ipython_console_highlighting',
     'IPython.sphinxext.ipython_directive',