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keith frazier
Python Development Techdegree Student 5,771 PointsUnique Set vs Redundant List
I am unsure how the list works at 10:19. The other loops he creates are pretty self explanatory like how the grid with ranges 1-4 and 1-10 had a combination of each case in each range. Can someone explain this loop a little better, specifically why each number is generated?
[round(x,y) for y in range(1, 11) for x in range(2, 21)]
In the video he gets a list that has many repeating numbers like 1, 1, 1, 1, 2, 2, 2, 2, etc. But when I run the code myself I get the following:
>> [round(x,y) for y in range(1,11) for x in range(2,21)]
[2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 2, 3,
4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 2, 3, 4, 5,
6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]
None of the numbers repeat themselves right after each other. What is the difference in what the video is doing and what I am doing?
1 Answer
Chris Freeman
Treehouse Moderator 68,428 PointsIt seems you have a typo. Perhaps you meant round(x/y) instead of "round(x, y)". By using a comma, the second argument is the number of places to round to, but since x is always an integer, you always get itself back after the rounding. See docs.
Post back if you have more questions. Good luck!