PYTHON LESSON
map/filter/reduce
Functional tools transform streams of values.
Combine with pure helper functions.
Using reduce where loop is clearer.
Read this next
This lesson is about map/filter/reduce. You are in the Functional Programming part of the course.
Main idea:
Functional tools transform streams of values.
How to learn it: type a very small program first. Run it. Change one line and run again.
Tip:
Combine with pure helper functions.
Common mistake:
Using reduce where loop is clearer.
Your challenge:
Filter and transform sales numbers.
Scroll down to the challenge lab. Run your code there. When the output meets the task and the checks pass, press the green button to finish this topic.
Example code
Copy this example if it helps. Change it so it matches map/filter/reduce.
# Topic: map/filter/reduce
def main():
sample = "edit me"
# TODO: apply map/filter/reduce concept here
result = sample
print("Result:", result)
if __name__ == "__main__":
main()
Challenge
Filter and transform sales numbers.
Before you can finish: your output should include at least 16 characters; at least 1 non-empty line(s); no crash traceback—fix errors until the program runs cleanly.
Use Run. Read the output. Change your code until the task is done.
Starter reference
# Challenge starter for map/filter/reduce
def solve():
# Write your solution here
pass
print("Update solve() and run")Your code
The first Run may load Python in your browser (one-time). Later runs are faster.