Category: Python

import media

toy_story = media.Movie("Toy Story",
                        "A story of a boy and toys that come to life",
                        "http://upload.wikimedia.org/wikipedia/en/1/13/Toy_Story.jpg",
                        "https://www.youtube.com/watch?v=vwyZH85NQC4")
# print(toy_story.storyline)

avatar = media.Movie("Avatar",
                     "A marine on an alien planet",
                     "http://upload.wikimedia.org/wikipedia/id/b/b0/Avatar-Teaser-Poster.jpg",
                     "http://www.youtube.com/watch?v=-9ceBgWV8io")

print(avatar.storyline)
# avatar.show_trailer()

kiminonawa = media.Movie("Kimino na wa",
                         "Your Name is a 2016 Japanese anime fantasy film written and directed by Makoto Shinkai",
                         "https://myanimelist.cdn-dena.com/images/anime/7/79999.webp",
                         "https://www.youtube.com/watch?v=k4xGqY5IDBE")
kiminonawa.show_trailer()

media.py

import webbrowser

class Movie():
    def __init__(self, movie_title, movie_storyline, poster_image, trailer_youtube):
        self.title = movie_title
        self.storyline = movie_storyline
        self.poster_image_url = poster_image
        self.trailer_youtube_url = trailer_youtube

    def show_trailer(self):
        webbrowser.open(self.trailer_youtube_url)

import fresh_tomatoes
import media

brother = media.Movie("brother",
                        "Takeshi Kitano plays Yamamoto, a lone yakuza officer. Defeated in a war with a rival family, his boss killed, he heads to Los Angeles, California.",
                        "https://upload.wikimedia.org/wikipedia/en/a/a1/BrotherKitano.jpg",
                        "https://www.youtube.com/watch?v=AgjDYR6-DTU")
# print(toy_story.storyline)
outrage = media.Movie("Outrage",
                     "The film begins with a sumptuous banquet at the opulent estate of the Grand Yakuza leader Sekiuchi (Soichiro Kitamura), boss of the Sanno-kai, a huge organized crime syndicate controlling the entire Kanto region, and he has invited the many Yakuza leaders under his control.",
                     "https://upload.wikimedia.org/wikipedia/en/f/f4/Outrage-2010-poster.png",
                     "https://www.youtube.com/watch?v=EXLuvZY8bMU")

#print(avatar.storyline)
# avatar.show_trailer()

#kiminonawa = media.Movie("Kimino na wa",
#                         "Your Name is a 2016 Japanese anime fantasy film written and directed by Makoto Shinkai",
#                         "https://myanimelist.cdn-dena.com/images/anime/7/79999.webp",
#                         "https://www.youtube.com/watch?v=k4xGqY5IDBE")
#kiminonawa.show_trailer()

kids = media.Movie("Kids Return",
                             "The movie is about two high school dropouts, Masaru (Ken Kaneko) and Shinji (Masanobu Ando)",
                             "https://upload.wikimedia.org/wikipedia/en/a/a7/KidsReturnPoster.jpg",
                             "https://www.youtube.com/watch?v=MvY6JCFCrQk")

ratatouille = media.Movie("Ratatouille",
                             "storyline",
                             "http://upload.wikimedia.org/wikipedia/en/5/50/RatatouillePoster.jpg",
                             "https://www.youtube.com/watch?v=3YG4h5GbTqU")

midnight_in_paris = media.Movie("Midnight in Paris",
                             "storyline",
                             "http://upload.wikimedia.org/wikipedia/en/9/9f/Midnight_in_Paris_Poster.jpg",
                             "https://www.youtube.com/watch?v=JABOZpoBYQE")

hunger_games = media.Movie("Hunger Games",
                             "storyline",
                             "http://upload.wikimedia.org/wikipedia/en/4/42/HungerGamesPoster.jpg",
                             "https://www.youtube.com/watch?v=PbA63a7H0bo")

movies = [brother, outrage, kids, ratatouille, midnight_in_paris, hunger_games]
fresh_tomatoes.open_movies_page(movies)

documentation

>>> import turtle
>>> turtle.Turtle.__doc__
'RawTurtle auto-creating (scrolled) canvas.\n\n    When a Turtle object is created or a function derived from some\n    Turtle method is called a TurtleScreen object is automatically created.\n 

inheritance

class Parent():
    def __init__(self, last_name, eye_color):
        print("parent constructor called")
        self.last_name = last_name
        self.ey_color = eye_color

class Child(Parent):
    def __init__(self, last_name, eye_color, number_of_toys):
        print("child constructor called")
        Parent.__init__(self, last_name, eye_color)
        self.number_of_toys = number_of_toys
        

#billy_cyrus = Parent("Cyrus","blue")
#print(billy_cyrus.last_name)

myley_crus = Child("cryus", "blue", 5)
print(myley_crus.last_name)
print(myley_crus.number_of_toys)

http://www.wdylike.appspot.com/ is a site judge it contain curse word in it.

import urllib

def read_text():
   quotes = open(r"C:\Users\hoge\Desktop\controller\movie_quote.txt")
   contents_of_file = quotes.read()
   # print(contents_of_file)
   quotes.close()
   check_profanity(contents_of_file)

def check_profanity(text_to_check):
    connection = urllib.urlopen("http://www.wdylike.appspot.com/?q="+text_to_check)
    output = connection.read()
    # print(output)
    connection.close()
    if "true" in output:
        print("Profanity Alert!")
    elif "false" in output:
        print("This document has no curse words")
    else:
        print("Could not scan the document properly.")
    
read_text()

when you write python, google style guide would help coding.
https://google.github.io/styleguide/pyguide.html

import turtle

def draw_star(some_turtle):
    for i in range(1, 6):
        some_turtle.forward(100)
        some_turtle.right(144)

def draw_art():
    window = turtle.Screen()
    window.bgcolor("red")
    
    brad = turtle.Turtle()
    brad.shape("arrow")
    brad.color("blue")    
    brad.speed(5)
    for i in range(1, 11):
        draw_star(brad)
        brad.right(36)

    # angie = turtle.Turtle()
    # angie.shape("arrow")
    # angie.color("blue")
    # angie.circle(100)

    # triangle = turtle.Turtle()
    # angie.shape("arrow")
    # angie.color("blue")
    
    # for x in range(0, 3):
    #    brad.forward(100)
    #    brad.right(240)

    window.exitonclick()

draw_art()

open file and read the content from the file.
python library: https://docs.python.org/2/library/functions.html#open

below code “quotes” indicate the object another word instance.

def read_text():
   quotes = open(r"C:\Users\hoge\Desktop\controller\movie_quote.txt")
   contents_of_file = quotes.read()
   print(contents_of_file)
   quotes.close()
   
read_text()

using python build-in function

def multi_func(a, b):
    return a*b

items = [1,3, 5, 7]
def reduce_value():
    value = reduce(multi_func, items)
    print(value)

reduce_value()

105
>>>

time alert program which call you tube video.

import time
import webbrowser

total_breaks = 3
break_count = 0

print("this program start on"+time.ctime())
while(break_count < total_breaks):
    time.sleep(2*60*60)
    webbrowser.open("https://www.youtube.com/watch?v=PDSkFeMVNFs")
    break_count = break_count + 1

get a file from computer and rename file name.In this case, remove the number of file name.

import os
def rename_files():
    #(1)get file names from a folder
    file_list = os.listdir(r"C:\Users\prank")
    #print(file_list)
    save_path = os.getcwd()
    print(save_path)
    os.chdir(r"C:\Users\prank")
    #(2)for each file, rename filename
    for file_name in file_list:
       os.rename(file_name, file_name.translate(None, "0123456789"))
    os.chdir(save_path)

rename_files()

def crawl_web(seed): # returns index, graph of outlinks
    tocrawl = [seed]
    crawled = []
    graph = {}  # <url>:[list of pages it links to]
    index = {} 
    while tocrawl: 
        page = tocrawl.pop()
        if page not in crawled:
            content = get_page(page)
            add_page_to_index(index, page, content)
            outlinks = get_all_links(content)
            graph[page] = outlinks
            union(tocrawl, outlinks)
            crawled.append(page)
    return index, graph

def ancestors(genealogy, person):
  if person in genealogy:
    parents = genealogy[person]
    result = parents
    for parent in parents:
      result = result + ancestors(genealogy, parent)
    return result
    
  return []

Blaise Pascal Triangle

def make_next_row(row):
  result = []
  prev = 0
  for e in row:
    result.append(e + prev)
    prev = e
  result.append(prev)
  return result

def triangle(n):
  result = []
  current = [1]
  for unused in range(0, n):
    result.append(current)
    current = make_next_row(current)
    
  return result

-base cases
fibonacci(0)=0
fibonacci(1)=1

-recursive case
fibonacci(n) = fibonacci(n-1)+fibonacci(n-2)
n > 1

A procedure, fibonacci, that takes a natural number as its input, and returns the value of that fibonacci number.

def fibonacci(n):
    if n == 0:
      return 0
    if n == 1:
      return n
    return fibonacci(n-1) + fibonacci(n-2)

fibonacci has interesting feature below
fibo(x) = fibo(x-n-1)

More faster fibonacci procedure using for loop.

def fibonacci(n):
    current = 0
    after = 1
    for i in range(0, n):
      current, after = after, current + after
    return current

mass_of_earth = 5.9722 * 10**24
mass_of_rabbit = 2

n = 1
while fibonacci(n) * mass_of_rabbit < mass_of_earth:
  n = n + 1
print n, fibonacci(n)

- Ranking web pages as popularity
popularity(p) = # of people who are friends with p
popularity(p) = Σ popularity(f), f E friends of p

def popularity(p):
score = 0
for f in friends(p):
score = score + popularity(f)
return score

factorial(n) = n*(n-1)*(n-2)*…1

factorial(n)=1
factorial(n)=n*factorial(n-1)

A procedure, factorial, that takes a natural number as its input, and returns the number of ways to arrange the input number of items.

def factorial(n):
 if n == 0:
   return 1
 else:
   return n * factorial(n-1)

Palindromes:match the first and last string, such as level.
A procedure is_palindrome, that takes as input a string, and returns a Boolean indicating if the input string is a palindrome.

def is_palindrome(s):
  if s == "":
    return True
  else:
    if s[1] == s[-1]:
        return is_palindrome(s[1:-1])
    else:
        return false

Another way, using for loop, to write palindrome procedure.

def iter_palindrome(s):
  for i in range(0, len(s)/2):
    if s[i] != s[-(i + 1)]:
      return False
  return True

String: sequence of characters, immutable
ex. ‘hello’, s[i] is i th character in S
List: list of elements, mutable
ex. [‘alpha’, 23], p[i] is i th element of p
Dictionary: set of pairs, mutable
ex. {‘hydrogen’: 1, ‘helium’: 23, d[k], k is whatever the key value
ex. d[k] = v, is similar to the update.

Here is a example to use dictionary

elements = {'hydrogen':1, 'helium':2, 'carbon':6 }
elements['lithimu'] = 3
elements['nitrogen'] = 8
elements['nitrogen'] = 7
print elements['nitrogen']

population = {'Shanghai':17.8, 'Istanbul':13.3, 'Karachi':13.0, 'Mumbai':12.5 }

another example

elements = {}
elements['H'] = {'name': 'Hydrogen', 'number': 1, 'weight': 1.00794}
elements['He'] = {'name': 'Helium', 'number': 2, 'weight': 4.002602, 'noble gas': True}
print elements['He']['name']

procedure return a list of strings that break the source string up by the characters in the splitlist.

def split_string(source,splitlist):
  output = []
  atsplit = True
  for char in source:
    if char in splitlist:
      atsplit = True:
    else:
      if atsplit:
        output.append(char)
        atsplit = False
      else:
        output[-1] = output[-1] + char
    return output

cut duplicated url on index list

def add_to_index(index, keyword, url):
    for entry in index:
        if entry[0] == keyword:
            if not url in entry[1]:
            entry[1].append(url)
            return
    # not found, add new keyword to index
    index.append([keyword, [url]])

One way search engines rank pages is to count the number of times a searcher clicks on a returned link. This indicates that the person doing the query thought this was a useful link for the query, so it should be higher in the rankings next time.

def record_user_click(index,keyword,url):
  urls = lookup(index, keyword)
  if urls:
    for entry in urls:
      if entry[0] == url:
        entry[1] = entry[1] + 1
      
def add_to_index(index,keyword,url):
  for entry in index:
    for entry[0] == keyword:
      for elment in entry[1]:
        if element[0] = url:
          return
      entry[1].append([url,0])
      return
  index.append([keyword,[[url,0]]])

How program run fast making things fast. It depends algorithm analysis that most programmer spend time in procedure, well defined sequence of steps that can be executed mechanically. So gatta think about time and memory said cost of computer.

time consuming

import time

def time_execution(code):
  start = time.clock()
  result = eval(code)
  run_time = time.clock() - start
  return result, run_time

def spin_loop(n):
  i = 0
  while i < n:
    i = i + 1
    
print time_execution('2 ** 10')


Python 2.7.10 (default, Jul 14 2015, 19:46:27)
[GCC 4.8.2] on linux
(1024, 1.6000000000002124e-05)

print time_execution('spin_loop(10000000)')
(None, 0.33208099999999996)

Creating an Empty Hash Table, make_hashtable, that takes as input a number, nbuckets, and returns an empty hash table with nbuckets empty buckets.

def make_hashtable(nbuckets):
  i = 0
  table = []
  while i < nbuckets:
    table.append([])
    i = i + 1
  return table

for loop, we do not need variable like i.

def make_hashtable(nbuckets):
  i = 0
  table = []
  for unused < range(0, nbuckets):
    tabale.append([])
  return table

Update hashtable, if key is already in the table, change the value to the new value.

def hashtable_update(htable,key,value):
    bucket = hashtable_get_bucket(htable, key)
    for entry in hashtable
        if entry[0] == key:
          entry[1] = value
    bucket.append([key, value])

If the keyword is already in the index, add the url to the list of urls associated with that keyword. If the keyword is not in the index, add an entry to the index: [keyword,[url]]

index = []

def add_to_index(index,keyword,url):
    for entry in index:
      if entry[0] == keyword:
        entry[1].append(url)
        return
    index.append([keyword,[url]])

Return a list of the urls associated with the keyword. If the keyword is not in the index, the procedure return an empty list.

def lookup(index,keyword):
    for entry in index:
      if entry[0] == keyword:
        return entry[1]
    return[]

split()

quote = "In Washington, it's dog eat dog. In academia...."
quote.split()

update the index to include all of the word occurences found in the page content by adding the url to the word’s associated url list.

def add_to_index(index,keyword,url):
    for entry in index:
        if entry[0] == keyword:
            entry[1].append(url)
            return
    index.append([keyword,[url]])

def add_page_to_index(index,url,content):
    words = content.split()
    for word in words:
    add_to_index(index, word, url)

python code getting url from internet

def get_page(url):
  try:
    import urllib
    return urllib.urlopen(url).read()
  except:
    return ""

The meaning of Latency and bandwidth is close but different.Latency is time it takes message to get from source to destination. Bandwidth is amount of information that can be transmitted per unit time. It is said mbps, bit per second.
internet-speed-test

Define traceroute

[vagrant@localhost ~]$ traceroute www.whitehouse.gov
traceroute to www.whitehouse.gov (184.26.234.167), 30 hops max, 60 byte packets
 1  10.0.2.2 (10.0.2.2)  0.474 ms  0.397 ms  0.302 ms
 2  10.0.2.2 (10.0.2.2)  88.120 ms  87.848 ms  87.469 ms

comparing traceroute in windows

PS C:\Users\hoge> tracert www.udacity.com

apollo-mesos-elb-berlioz2-prod-885022263.us-west-2.elb.amazonaws.com [52.40.117.247] へのルートをトレー
経由するホップ数は最大 30 です:

  1    94 ms     6 ms     6 ms  192.168.179.1
  2     *        *        *     要求がタイムアウトしました。
  3     *        *        *     要求がタイムアウトしました。
  4    65 ms    57 ms    78 ms  172.25.21.178
  5    61 ms    64 ms    65 ms  172.25.153.3
  6    74 ms    91 ms    63 ms  172.25.153.46
  7    65 ms    65 ms    67 ms  chyISN001.bb.kddi.ne.jp [27.85.176.181]
  8    87 ms    69 ms    71 ms  obpBBAC03.bb.kddi.ne.jp [27.90.191.254]
  9    59 ms    94 ms    59 ms  obpjbb205.int-gw.kddi.ne.jp [125.53.98.93]
 10   248 ms   238 ms   234 ms  pajbb001.int-gw.kddi.ne.jp [203.181.100.194]
 11   201 ms   228 ms   174 ms  ix-pa9.int-gw.kddi.ne.jp [111.87.3.74]
 12   190 ms   189 ms   178 ms  72.21.221.125
 13   210 ms   194 ms   202 ms  54.240.243.50
 14   197 ms   179 ms   179 ms  54.240.243.55
 15   204 ms   197 ms   204 ms  205.251.232.116
 16   264 ms   247 ms   197 ms  52.93.12.76
 17   209 ms   196 ms   196 ms  52.93.12.73
 18   244 ms   202 ms   217 ms  52.93.12.144
 19   203 ms   196 ms   195 ms  52.93.12.165
 20   208 ms   196 ms   197 ms  52.93.13.67
 21     *        *        *     要求がタイムアウトしました。
 22     *        *        *     要求がタイムアウトしました。
 23     *        *        *     要求がタイムアウトしました。
 24     *        *        *     要求がタイムアウトしました。
 25     *        *        *     要求がタイムアウトしました。
 26     *        *        *     要求がタイムアウトしました。
 27     *        *        *     要求がタイムアウトしました。
 28     *        *        *     要求がタイムアウトしました。
 29     *        *        *     要求がタイムアウトしました。
 30     *        *        *     要求がタイムアウトしました。

トレースを完了しました。
PS C:\Users\hoge> tracert www.mit.edu

e9566.dscb.akamaiedge.net [23.9.161.192] へのルートをトレースしています
経由するホップ数は最大 30 です:

  1  2662 ms     3 ms     7 ms  192.168.179.1
  2     *        *        *     要求がタイムアウトしました。
  3     *        *        *     要求がタイムアウトしました。
  4    71 ms    62 ms    83 ms  172.25.21.178
  5    86 ms    72 ms    63 ms  172.25.153.3
  6    74 ms    58 ms    79 ms  172.25.153.46
  7    72 ms    57 ms    79 ms  chyISN001.bb.kddi.ne.jp [27.85.176.181]
  8    84 ms    77 ms    79 ms  27.85.132.197
  9    83 ms    78 ms    78 ms  27.85.134.50
 10    89 ms    79 ms    79 ms  210.132.124.62
 11    77 ms    63 ms    73 ms  a23-9-161-192.deploy.static.akamaitechnologies.com [23.9.161.192]