Data Science Portfolio

Loops

For Loop

Create a list of numbers

# Create a list of numbers
nums = [1, 2, 3, 4, 5]
print(nums)

[1, 2, 3, 4, 5]

Use a for loop to print each element

# Loop through the list and print out each number
for i in range(len(nums)):
    print(nums[i])

1
2
3
4
5

While Loop

Initialize i

i = 0

Use a while loop to print each element

• Manually increment i variable inside loop
• Loop will run until it meets a stopping condition
• Stopping condition: when i is equal to the length of the list

while i != len(nums):
    print(nums[i])
    i += 1

1
2
3
4
5

Break Statement

Initialize i

i = 0

Use break to exit the loop early once i reaches a particular value

• Loop will terminate once it encounters break statement

while i != len(nums):
    if i == 3:
        'Exiting the loop.'
        break
    print(nums[i])
    i += 1

1
2
3

Continue Statement

Initialize i

i = 0

Use continue to skip over a particular index

• Skips over every subsequent line of code in the current loop iteration
• The program jumps to the next iteration of the loop
• Care must be taken to avoid infinite loops

while i != len(nums):
    if i == 3:
        'Skipping element at index 3.'
        i += 1
        continue
    print(nums[i])
    i += 1

1
2
3
5