Andre Duvoisin on Twitter: "Programming Puzzle: Many fitness apps have a problem storing my weight (120 lbs). They always round down to 119 or 119.9. 121 works. Why is this? 🤔 I thought there could be something wonky with floating point numbers, but even a 16-bit short float has plenty of room for 120."

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‏ @andreduvoisin

Programming Puzzle: Many fitness apps have a problem storing my weight (120 lbs). They always round down to 119 or 119.9. 121 works. Why is this? I thought there could be something wonky with floating point numbers, but even a 16-bit short float has plenty of room for 120.

6:56 PM - 17 Dec 2019

5 replies

1. Anna Funk‏ @annafunk 17 Dec 2019
  Replying to @andreduvoisin
  
  I wonder if it's not a programming problem. Multiples of 10 are goals, and Fitness apps don't want people to sit at their goals. Would definitely be a dark pattern, but I wouldn't be shocked at all.
  
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1. Neil Shapiro‏ @shapirowned 17 Dec 2019
  Replying to @andreduvoisin
  
  Weird flex but ok
  
  3 likes
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1. ultraheroic‏ @ultraheroicHS 17 Dec 2019
  Replying to @andreduvoisin
  
  Or they convert to metric unit first before storing (with an constant with several digits) and than you have a floating point problem or loss of precision.
  
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1. Lowell A. Doringo‏ @LoloDoringo 17 Dec 2019
  Replying to @andreduvoisin
  
  Now you’re just bragging
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1. Brit Gardner‏ @britg 18 Dec 2019
  Replying to @andreduvoisin
  
  Definitely a floating point issue!pic.twitter.com/CiLPyx9oxf
  
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