Question

Python (Using for reference please comment which is which!)

Exercise 1: Store Unique Words as Dictionary Keys

Write a program that stores unique words as keys in a dictionary. Don't worry about upper/lowercase for now (i.e., it's ok for you to have separate entries for "The" and "the"), and just assign 1 as the value for each key.

1. Use an input loop (while loop with an input function) to accepts values putting them into the dictionary until the user enters "done."
2. After finishing the loop, print the contents of the dictionary.

Hint: You can use the in operator as a fast way to check whether a string is in the dictionary.

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Put code for Exercise 1 here

Exercise 2: Maintain word counts for unique words from (Ex 1)

A common use-case for dictionaries is to store word counts. Let's modify our program from Exercise 1 to store the count for each unique word. Let's name the dictionary word_counts.

This means you need to initialize the count value to 1 for a particular word if you see it for the first time (i.e., it's not already in word_counts) and update the count (by adding 1 to it) if the word is already present in word_counts.

Hints:

• You can reuse Exercise 1 for this part
• You can also look at Part 2 of project 2

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#Put code for Exercise 2 here

Exercise 3: Populate a list from a file of individual records

For the noisewords file (also called stopwords), each record in the file contains a different word. For this assignment:

1. create a function that takes in the name of a file and returns a list. If the file is not found, the list returned should contain one entry that is a message that indicates the file is was not accessed.
2. Create a function that will remove noise words from a long string and then return just the other words
3. Create a test loop where the user can enter a phrase and that phrase is sent to the function and the results returned and printed for the user to see.

Hints:

• You will be creating a list by reading successive records in a file rather than a single record as most people did in the project.
• You will need to split the string into a list in the function and then recreate the single string before returning it after the noise words are removed.
• You will probably use the .remove() function for the list, although there are other ways.

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# Put code for Exercise 3 here

Exercise 4: Process a text file removing characters and "noise" words.

This program will work very much like Part four of Project 2 where three files are read in:

• A document file about a topic relevant to the Pod
• A .txt file with a list of characters to be removed
• A .txt file with a list of "noise" words to be removed.

In addition to calling a function to remove characters and replace them with spaces, this program should count how many times different words are used in the document in a dictionary. Words that are all CAPS, all numeric, or are in the "noise" words file (ex: the, of, and, etc.) are not to be put into the dictioary of counts. Only those words that have unique content are to be put into the final dictionary count.

At the end of the program, print out the words in dictionary in descending order of the count.

Hints:

• You CAN reuse your Project 2 code for this assignment you till need to update it.
• You should find a noise-word.txt file on ELMS to use
• You will need the sorted method for the Dictionary

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#Put code for Exercise 4 here

Answer 1

1.

"""
Python version : 3.6
Python program that stores unique words as keys in a dictionary.
"""

# create an empty dictionary
unique_keys = {}

word = ""
# loop that continues until user enters "done" to exit
while word != "done":
   # input the word
   word = input("Enter a word ('done' to exit): ")
  
   # check if user wants to exit
   if word != "done":
       # if word is not inserted in dictionary, insert it with value as 1
       if word not in unique_keys:
           unique_keys[word] = 1

# display the contents of the dictionary
print(unique_keys)
#end of program

Code Screenshot:

Output:

2.

"""
Python version : 3.6
Python program that stores unique words as keys and its frequency as value in a dictionary.
"""

# create an empty dictionary
word_counts = {}

word = ""

# loop that continues until user enters "done" to exit
while word != "done":
  
   # input the word
   word = input("Enter a word ('done' to exit): ")
  
   # check if user wants to exit
   if word != "done":
      
       # if word is found in dictionary, increment its value by 1
       if word in word_counts:
           word_counts[word] += 1
      
       else:   # if word is not found in dictionary, insert it with value as 1
           word_counts[word] = 1
          

# display the contents of the dictionary
print(word_counts)
#end of program

Code Screenshot:

Output: