python-classes.py

print(
  '-----------------------------------------\n'\
  'Python Education || Documentation - Classes\n'\
  '-----------------------------------------\n'
  )

print(
  'Task:\n'\
  '-----------------------------------------\n'\
  'Write a Python program to test all available functionalities and code samples from the official documentation.\n'
  )

print(
  'Solution:\n'\
  '-----------------------------------------'\
  )

import doctest
import unittest

#Default function for handling execution loop:
def execution_loop():
  data = int(input("Do you want to try again ? Enter [1] - for continue / [0] - for quit :"))
  if data == 1:
    return True
  elif data == 0:
    return False
  else:
    print("Error: your entered incorrect command. Please, try again...")
    execution_loop()

#Function for testing definition of function outside of the class:
def fl(self, x, y):
    return min(x, x+y)

class C:
    f = fl
    def g(self):
        return 'I\'m a function "g".'
    h = g

#Initializing a new Reverse class:
class Reverse:
  def __init__(self, data):
    self.data = data
    self.index = len(data)

  def __iter__(self):
    return self

  def __next__(self): 
    if self.index == 0:
      raise StopIteration
    self.index = self.index - 1
    return self.data[self.index]

#Initializing a new test statistical function for unit testing of the code:
class TestStatisticalFunctions(unittest.TestCase):
  def test_average(self):
    self.assertEqual(average([20, 30, 70]), 40.0)
    self.assertEqual(round(average([1, 5, 7]), 1), 4.3)
    with self.assertRaises(ZeroDivisionError):
      average([])
    with self.assertRaises(TypeError):
      average(20, 30, 70)

#Function for testing iterators:
def iterators_func():
  print('Iterators function was called:')
  print('Testing for loop statement with iterators:')
  for element in [1, 2, 3]:
    print(element)
  for element in (4, 5, 6):
    print(element)
  for key in {'one': 1, 'two': 2, 'three': 3}:
    print(key)
  for char in "789":
    print(char)
  for line in open("./python-classes.txt"):
    print(line, end='')

  print('\nLooping over a backward sequence:\n')

  test_string = 'vr player'
  it = iter(test_string)
  print(it)
  print(next(it))
  print(next(it))
  print(next(it))

  print('\nDisplaying a backward sequence:\n')
  rev = Reverse('spam')
  iter(rev)
  for char in rev:
    print(char)

#Function for handling reverse displaying:
def handleReverseDisplay(data):
  print('Using generators for displaying reverse data:')
  for char in reverse(data):
    print(char)

#Function for reverse displaying:
def reverse(data):
  for index in range(len(data)-1, -1, -1):
    yield data[index]

#Function for testing generator expressions:
def generator_expressions():
  from math import pi, sin
  print('Sum of squares:\n')
  print(sum(i*i for i in range(10)))
  xvec = [10, 20, 30]
  yvec = [7, 5, 3]
  print('Dot product:\n')
  print(sum(x*y for x,y in zip(xvec, yvec)))
  sine_table = { x: sin(x*pi/180) for x in range(0, 91) }
  data = input("Enter your custom text for testing generator expressions:\n>>> ")
  data_output = list(data[i] for i in range(len(data)-1, -1, -1))
  print(data_output)

#Function for testing quality of the code using 'doctest' module:
def doctest_quality_control(values):
  return sum(values) / len(values)


#Default parameter for handling execution loop:
again_exec = True
counter_exec = 0

#Default loop for handling execution:
while again_exec:
  iterators_func()
  user_input = input('Please, enter your custom text for testing reverse displaying:\n>>> ')
  handleReverseDisplay(user_input)
  generator_expressions()
  print('The arithmetic mean of a list of numbers 20, 30 ,70: ')
  doctest_quality_control([20, 30, 70])
  #doctest the code:
  doctest.testmod()
  #unittest the code:
  unittest.main()
  again_exec = execution_loop()
  counter_exec = counter_exec + 1

  #The end of execution:
  if again_exec == False:
    print("Program was executed: ",counter_exec, ' times.')
    break


print(
  '\n-----------------------------------------\n'\
  'Copyright 2019 Vladimir Pavlov. All Rights Reserved.\n'\
  '-----------------------------------------'
  )