Title: Applying Functions To List Items
Slug: applying_functions_to_list_items
Summary: Applying Functions To List Items
Date: 2016-05-01 12:00
Category: Python
Tags: Basics
Authors: Chris Albon

Create a list of regiment names



In [23]:

    
regimentNames = ['Night Riflemen', 'Jungle Scouts', 'The Dragoons', 'Midnight Revengence', 'Wily Warriors']

Using A For Loop

Create a for loop goes through the list and capitalizes each



In [26]:

    
# create a variable for the for loop results
regimentNamesCapitalized_f = []

# for every item in regimentNames
for i in regimentNames:
    # capitalize the item and add it to regimentNamesCapitalized_f
    regimentNamesCapitalized_f.append(i.upper())
    
# View the outcome
regimentNamesCapitalized_f









    Out[26]:





['NIGHT RIFLEMEN',
 'JUNGLE SCOUTS',
 'THE DRAGOONS',
 'MIDNIGHT REVENGENCE',
 'WILY WARRIORS']

Using Map()

Create a lambda function that capitalizes x



In [25]:

    
capitalizer = lambda x: x.upper()

Map the capitalizer function to regimentNames, convert the map into a list, and view the variable



In [18]:

    
regimentNamesCapitalized_m = list(map(capitalizer, regimentNames)); regimentNamesCapitalized_m









    Out[18]:





['NIGHT RIFLEMEN',
 'JUNGLE SCOUTS',
 'THE DRAGOONS',
 'MIDNIGHT REVENGENCE',
 'WILY WARRIORS']

Using List Comprehension

Apply the expression x.upper to each item in the list called regiment names. Then view the output



In [22]:

    
regimentNamesCapitalized_l = [x.upper() for x in regimentNames]; regimentNamesCapitalized_l









    Out[22]:





['NIGHT RIFLEMEN',
 'JUNGLE SCOUTS',
 'THE DRAGOONS',
 'MIDNIGHT REVENGENCE',
 'WILY WARRIORS']