Python basic programs...

Python basic programs-1

1 line: Output

print 'Hello, world!'

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2 lines: Input, assignment

name = raw_input('What is your name?\n')

print 'Hi, %s.' % name

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3 lines: For loop, built-in enumerate function, new style formatting

friends = ['john', 'pat', 'gary', 'michael']

for i, name in enumerate(friends):

    print "iteration {iteration} is {name}".format(iteration=i, name=name)

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4 lines: Fibonacci, tuple assignment

parents, babies = (1, 1)

while babies < 100:

    print 'This generation has {0} babies'.format(babies)

    parents, babies = (babies, parents + babies)

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5 lines: Functions

def greet(name):

    print 'Hello', name

greet('Jack')

greet('Jill')

greet('Bob')

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6 lines: Import, regular expressions

import re

for test_string in ['555-1212', 'ILL-EGAL']:

    if re.match(r'^\d{3}-\d{4}$', test_string):

        print test_string, 'is a valid US local phone number'

    else:

        print test_string, 'rejected'

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7 lines: Dictionaries, generator expressions

prices = {'apple': 0.40, 'banana': 0.50}

my_purchase = {

    'apple': 1,

    'banana': 6}

grocery_bill = sum(prices[fruit] * my_purchase[fruit]

                   for fruit in my_purchase)

print 'I owe the grocer $%.2f' % grocery_bill

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8 lines: Command line arguments, exception handling

# This program adds up integers in the command line

import sys

try:

    total = sum(int(arg) for arg in sys.argv[1:])

    print 'sum =', total

except ValueError:

    print 'Please supply integer arguments'

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9 lines: Opening files

# indent your Python code to put into an email

import glob

# glob supports Unix style pathname extensions

python_files = glob.glob('*.py')

for file_name in sorted(python_files):

    print '    ------' + file_name

    with open(file_name) as f:

        for line in f:

            print '    ' + line.rstrip()

    print

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10 lines: Time, conditionals, from..import, for..else

from time import localtime

activities = {8: 'Sleeping',

              9: 'Commuting',

              17: 'Working',

              18: 'Commuting',

              20: 'Eating',

              22: 'Resting' }

time_now = localtime()

hour = time_now.tm_hour

for activity_time in sorted(activities.keys()):

    if hour < activity_time:

        print activities[activity_time]

        break

else:

    print 'Unknown, AFK or sleeping!'