wrdcnt.py

# Simple program to get a word count of a phrase
phrase = raw_input("Enter a phrase with no punctuation: ")
print

# Use lower() and split() to create a list of lower case words
phraseList = phrase.lower().split(" ")
print "Created a lowercase list of words:", ", ".join(phraseList)
print

# Create a set from that list. Sets eliminate duplicates, which helps us
phraseSet = set(phraseList)
print "Used the list to create a set of unique words:", ", ".join(phraseSet)
print

# Use list comprehension to create a new list matrix (list of lists) each containing each word and its count.
# The count comes from the phrase list, and the words come from the phrase set so we only get one of each word
wordCounts = [[word,phraseList.count(word)] for word in phraseSet]

print "List comprehension created our unsorted word count using the list and set:"
for each in wordCounts:
  print each[1],"-",each[0]
print

# Sort the word count by word. Straight forward sort
wordCountsByWord = sorted(wordCounts)

print "Sorted By Word: "
for each in wordCountsByWord:
  print each[0],"-",each[1]
print

# Sort the word count by count descending (reverse). In this case we need to tell sort to sort
# using the second element of each sublist. We do this using the key parameter and lambda function
wordCountsByCount = sorted(wordCounts,key=lambda x:x[1],reverse=True)

print "Sorted By Count: "
for each in wordCountsByCount:
  print each[1],"-",each[0]
print

# We could also do everything in one shot - but it's not going to be as readable
wordCountsOneShot = sorted([[word,phrase.lower().split(" ").count(word)] for word in set(phrase.lower().split(" "))],key=lambda x:x[1],reverse=True)
print wordCountsOneShot


# End
phrase = raw_input("press ENTER to exit. ")