12.7. Exercises¶

Write a program that allows the user to enter a string. It then prints a table of the letters of the alphabet in alphabetical order which occur in the string together with the number of times each letter occurs. Case should be ignored. A sample run of the program might look this this:
Please enter a sentence: ThiS is String with Upper and lower case Letters. a 2 c 1 d 1 e 5 g 1 h 2 i 4 l 2 n 2 o 1 p 2 r 4 s 5 t 5 u 1 w 2 $
x = input("Enter a sentence") x = x.lower() # convert to all lowercase alphabet = 'abcdefghijklmnopqrstuvwxyz' letter_count = {} # empty dictionary for char in x: if char in alphabet: # ignore any punctuation, numbers, etc if char in letter_count: letter_count[char] = letter_count[char] + 1 else: letter_count[char] = 1 keys = letter_count.keys() keys.sort() for char in keys: print(char, letter_count[char])
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Give the Python interpreter’s response to each of the following from a continuous interpreter session:
1. ```
>>> d = {'apples': 15, 'bananas': 35, 'grapes': 12}
>>> d['banana']
```
2. ```
>>> d['oranges'] = 20
>>> len(d)
```
3. ```
>>> 'grapes' in d
```
4. ```
>>> d['pears']
```
5. ```
>>> d.get('pears', 0)
```
6. ```
>>> fruits = d.keys()
>>> fruits.sort()
>>> print(fruits)
```
7. ```
>>> del d['apples']
>>> 'apples' in d
```
Be sure you understand why you get each result. Then apply what you have learned to fill in the body of the function below:
def add_fruit(inventory, fruit, quantity=0): pass # make these tests work... # new_inventory = {} # add_fruit(new_inventory, 'strawberries', 10) # test('strawberries' in new_inventory, True) # test(new_inventory['strawberries'], 10) # add_fruit(new_inventory, 'strawberries', 25) # test(new_inventory['strawberries'] , 35)

Write a program called alice_words.py that creates a text file named alice_words.txt containing an alphabetical listing of all the words, and the number of times each occurs, in the text version of Alice’s Adventures in Wonderland. (You can obtain a free plain text version of the book, along with many others, from http://www.gutenberg.org.) The first 10 lines of your output file should look something like this

Word Count

a 631

a-piece 1

abide 1

able 1

about 94

above 3

absence 1

absurd 2

How many times does the word, alice, occur in the book? If you are writing this in the activecode window simply print out the results rather than write them to a file.
f = open('alice.txt', 'r') count = {} for line in f: for word in line.split(): # remove punctuation word = word.replace('_', '').replace('"', '').replace(',', '').replace('.', '') word = word.replace('-', '').replace('?', '').replace('!', '').replace("'", "") word = word.replace('(', '').replace(')', '').replace(':', '').replace('[', '') word = word.replace(']', '').replace(';', '') # ignore case word = word.lower() # ignore numbers if word.isalpha(): if word in count: count[word] = count[word] + 1 else: count[word] = 1 keys = count.keys() keys.sort() # save the word count analysis to a file out = open('alice_words.txt', 'w') for word in keys: out.write(word + " " + str(count[word])) out.write('\n') print("The word 'alice' appears " + str(count['alice']) + " times in the book.")
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What is the longest word in Alice in Wonderland? How many characters does it have?

Here’s a table of English to Pirate translations

English	Pirate
sir	matey
hotel	fleabag inn
student	swabbie
boy	matey
madam	proud beauty
professor	foul blaggart
restaurant	galley
your	yer
excuse	arr
students	swabbies
are	be
lawyer	foul blaggart
the	th’
restroom	head
my	me
hello	avast
is	be
man	matey

Write a program that asks the user for a sentence in English and then translates that sentence to Pirate.

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