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 why it's not printing? nickto21 Unladen Swallow Posts: 2 Threads: 1 Joined: Aug 2019 Reputation: 0 Likes received: 0 #1 Aug-15-2019, 10:59 PM Hey all, Im working through "The Self-taught programmer" by Cory Althoff. I'm doing the exercises at the end of chapter 2, and i'm having two difficulties. 1. I'm suppose to "create a program that divides two variables and prints the remainder." When I input "100 % 15" into the shell, I get output of "10", which is what I wanted. But when I input the exact same into a file, and then run module, I just get a restart message in the shell. how do I get the file to print the remainder in the shell? 2. Why is "10 // 0.1" giving the answer "99.0" , but "100 // 1" is giving answer 100? Both should be 100, so why 99.0 then? Thank you, Steve ichabod801 Bunny Rabbit Posts: 3,850 Threads: 84 Joined: Sep 2016 Reputation: 231 Likes received: 1164 #2 Aug-15-2019, 11:11 PM 1. If you are executing from a file, you need the print() function to display output. So `print(100 % 15)` 2. I'm not sure. I would guess it's a floating point error. Fractional numbers are not stored perfectly in Python (or most other languages). So I would guess 10 // 0.1 is giving something close to but not quite 100 before the integer truncation happens. However, 10 / 0.1 gives the correct answer of 100.0, so I'm not sure about that. Craig "Ichabod" O'Brien - xenomind.com I wish you happiness. Recommended Tutorials: BBCode, functions, classes, text adventures nickto21 Unladen Swallow Posts: 2 Threads: 1 Joined: Aug 2019 Reputation: 0 Likes received: 0 #3 Aug-15-2019, 11:26 PM thank you sir. scidam Posts: 541 Threads: 1 Joined: Mar 2018 Reputation: 71 Likes received: 76 #4 Aug-16-2019, 12:41 AM Floor division (//) in Python is almost the same as divmod builtin-function. You can see its implementation from here. Since `divmod(10, 0.1) = (99.0, 0.0999999....etc)` due to precision loss (as @ichabod801 mentioned above), you get `10//0.1=99.0 `. « Next Oldest | Next Newest »

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