Creating for loops and putting it into a function
- Since we just introduced a list, one of the most useful parts of a list is that they are an iterable
An iterable is a collection of data that you can move through using a for loop
For Loop Syntax in python
# Example 1
# For loop through a list of Numbers
lst = [1,2,3,4]
# "Iterate" through each number in the list
for number in lst:
# Print the number during each iteration
print(number)
You can iterate through many different objects including strings
This would be a good time to go ahead and play around with the following code segments in an IDE. Run each segment separately, and try to understand what is going on in each
# Example 2
# For loop through each letter in the string
string = 'Hello'
# Iterate through each letter in the string
for letter in string:
# Print each letter during the iterations
print(letter)
Printing words in a list
# Declare the list of words
lst_string = ['Hello','World']
# Iterate through each word in the list
for word in lst_string:
# Print the word during each iteration
print(word)
The range() Function
To loop through a set of code a specified number of times we can use the range() function.
The range() function returns a sequence of numbers, starting from 0 by default, and increments by 1 (by default), and ends at a specified number.
# Create an iterable using range
for x in range(6):
# print the value of the iterable during each loop
print(x)
- The range() function defaults to 0 as a starting value, however it is possible to specify the starting value by adding a parameter: range(2, 6), which means values from 2 to 6 (but not including 6):
# Start at number 2 and go through 5
for x in range(2,6):
print(x)
- The range() function defaults to increment the sequence by 1, however it is possible to specify the increment value by adding a third parameter:
range(2, 30, 3)
# Sequence starting at 2 going to 30 and jumping by 3
for x in range(2, 30, 3):
print(x)
