updated taxi simulator

concurrency/wikipedia/daypicts.py

@@ -28,12 +28,14 @@ import requests
 
 SAVE_DIR = 'downloaded/'
 
-#POTD_BASE_URL = 'http://en.wikipedia.org/wiki/Template:POTD/'
-POTD_BASE_URL = 'http://127.0.0.1:8001/Template-POTD/'
+HTTP_PORT = 8002
+POTD_BASE_URL = 'http://en.wikipedia.org/wiki/Template:POTD/'
+#POTD_BASE_URL = 'http://127.0.0.1:{}/Template-POTD/'.format(HTTP_PORT)
 
 REMOTE_PICT_BASE_URL = 'http://upload.wikimedia.org/wikipedia/'
-LOCAL_PICT_BASE_URL = 'http://127.0.0.1:8001/'
-PICT_BASE_URL = LOCAL_PICT_BASE_URL
+#LOCAL_PICT_BASE_URL = 'http://127.0.0.1:{}/'.format(HTTP_PORT)
+LOCAL_PICT_BASE_URL = REMOTE_PICT_BASE_URL
+PICT_BASE_URL = REMOTE_PICT_BASE_URL
 
 POTD_IMAGE_RE = re.compile(r'src="(//upload\..*?)"')
 PODT_EARLIEST_TEMPLATE = '2007-01-01'

concurrency/wikipedia/delay.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+vaurien --protocol http --proxy localhost:8002 --backend localhost:8001 \
+    --behavior 100:delay --behavior-delay-sleep .1

control/adder/adder.py

@@ -0,0 +1,42 @@
+import sys
+
+
+def ask():
+    prompt = '>'
+    while True:
+        response = input(prompt)
+        if not response:
+            return 0
+        yield response
+
+
+def parse_args():
+    yield from iter(sys.argv[1:])
+
+
+def fetch(producer):
+    gen = producer()
+    next(gen)
+    yield from gen
+
+
+def main(args):
+    if args:
+        producer = parse_args
+    else:
+        producer = ask
+
+    total = 0
+    count = 0
+    gen = fetch(producer())
+    while True:
+        term = yield from gen
+        term = float(term)
+        total += term
+        count += 1
+        average = total / count
+        print('total: {}  average: {}'.format(total, average))
+
+
+if __name__ == '__main__':
+    main(sys.argv[1:])

control/adder/coroadder0.py

@@ -0,0 +1,37 @@
+"""
+Closing a generator raises ``GeneratorExit`` at the pending ``yield``
+
+    >>> adder = adder_coro()
+    >>> next(adder)
+    >>> adder.send(10)
+    >>> adder.send(20)
+    >>> adder.send(30)
+    >>> adder.close()
+    -> total: 60  terms: 3  average: 20.0
+
+
+Other exceptions propagate to the caller:
+
+    >>> adder = adder_coro()
+    >>> next(adder)
+    >>> adder.send(10)
+    >>> adder.send('spam')
+    Traceback (most recent call last):
+      ...
+    TypeError: unsupported operand type(s) for +=: 'int' and 'str'
+
+
+"""
+
+def adder_coro(initial=0):
+    total = initial
+    num_terms = 0
+    try:
+        while True:
+            term = yield
+            total += term
+            num_terms += 1
+    except GeneratorExit:
+        average = total / num_terms
+        msg = '-> total: {}  terms: {}  average: {}'
+        print(msg.format(total, num_terms, average))

control/adder/yetanother.py

@@ -0,0 +1,47 @@
+import sys
+import collections
+
+Result = collections.namedtuple('Result', 'total average')
+
+def adder():
+    total = 0
+    count = 0
+    while True:
+        term = yield
+        try:
+            term = float(term)
+        except (ValueError, TypeError):
+            break
+        else:
+            total += term
+            count += 1
+    return Result(total, total/count)
+
+def process_args(coro, args):
+    for arg in args:
+        coro.send(arg)
+    try:
+        next(coro)
+    except StopIteration as exc:
+        return exc.value
+
+
+def prompt(coro):
+    while True:
+        term = input('+> ')
+        try:
+            coro.send(term)
+        except StopIteration as exc:
+            return exc.value
+
+
+def main():
+    coro = adder()
+    next(coro)  # prime it
+    if len(sys.argv) > 1:
+        res = process_args(coro, sys.argv[1:])
+    else:
+        res = prompt(coro)
+    print(res)
+
+main()

control/countdown_yf.py

@@ -0,0 +1,69 @@
+from time import sleep
+
+def countdown(n):
+    while n:
+        print('\tn ->', n)
+        yield n
+        n -= 1
+        sleep(1)
+
+def foo():
+    for i in range(6, 3, -1):
+        yield i
+    yield from countdown(3)
+
+#for j in foo():
+#    print('j ->', j)
+
+
+def squares(n):
+    yield from [i for i in range(n)]
+    yield from [i*i for i in range(n)]
+
+def squares_stupid(n):
+    for i in range(n):
+        yield i
+
+    for i in range(n):
+        yield i*i
+
+#for s in squares(10):
+#    print(s)
+
+
+def tokenize():
+    while True:
+        source = input('> ')
+        try:
+            obj = eval(source)
+        except BaseException:
+            print('*crash*')
+            return
+        try:
+            it = iter(obj)
+        except TypeError:
+            yield obj
+            return
+        else:
+            yield from it
+
+#g = tokenize()
+
+#for res in g:
+#    print(res)
+
+
+from concurrent.futures import Future
+
+def f():
+    f = future()
+
+def foo(fut):
+    print(fut, fut.result())
+f = Future()
+f.add_done_callback(foo)
+f.set_result(42)
+
+
+
+

control/simulation/taxi_sim.py

@@ -0,0 +1,61 @@
+import sys
+import random
+import collections
+import queue
+
+Event = collections.namedtuple('Event', 'time actor description')
+
+FIND_CUSTOMER_INTERVAL = 4
+TRIP_DURATION = 10
+
+
+def compute_delay(interval):
+    return int(random.expovariate(1/interval))
+
+
+def taxi_process(sim, ident):
+    trips = 3
+    for i in range(trips):
+        prowling_time = compute_delay(FIND_CUSTOMER_INTERVAL)
+        yield Event(sim.time + prowling_time, ident, 'customer picked up')
+
+        trip_time = compute_delay(TRIP_DURATION)
+        yield Event(sim.time + trip_time, ident, 'customer dropped off')
+
+
+class Simulator:
+
+    def __init__(self):
+        self.events = queue.PriorityQueue()
+        self.time = 0
+
+    def run(self, end_time):
+        taxis = [taxi_process(self, i) for i in range(3)]
+        while self.time < end_time:
+            for index, taxi in enumerate(taxis):
+                try:
+                    future_event = next(taxi)
+                except StopIteration:
+                    del taxis[index]  # remove taxi not in service
+                else:
+                    self.events.put(future_event)
+            if self.events.empty():
+                print('*** end of events ***')
+                break
+            event = self.events.get()
+            self.time = event.time
+            print('taxi:', event.actor, event)
+        else:
+            print('*** end of simulation time ***')
+
+
+def main(args):
+    if args:
+        end_time = int(args[0])
+    else:
+        end_time = 10
+    sim = Simulator()
+    sim.run(end_time)
+
+if __name__ == '__main__':
+    main(sys.argv[1:])