3 ms·
USA at some point had an anti-missile system that needed periodical reboots because it was originally designed for short deployments, so the floating point vari
by bombolo 4y ago
USA at some point had an anti-missile system that needed periodical reboots because it was originally designed for short deployments, so the floating point variable for the clock would start to lose precision after a while.
- saagarjha 4y agoWhich, of course, led to people dying when the drift was too great.
- perihelions 4y agoContext for those unfamiliar: https://www-users.cse.umn.edu/~arnold/disasters/patriot.html https://www-users.cse.umn.edu/~arnold/disasters/patriot.html https://en.wikipedia.org/wiki/MIM-104_Patriot#Failure_at_Dhahran https://en.wikipedia.org/wiki/MIM-104_Patriot#Failure_at_Dha... https://hn.algolia.com/?query=patriot%20missile https://hn.algolia.com/?query=patriot%20missile (HN threads)
- deleted 4y ago[deleted]
- mlindner 4y agoFixed point, not floating point. https://en.wikipedia.org/wiki/Fixed-point_arithmetic https://en.wikipedia.org/wiki/Fixed-point_arithmetic
- gcr 4y agoFloating point clocks do lose precision after long enough time though; see https://randomascii.wordpress.com/2012/02/13/dont-store-that-in-a-float/ https://randomascii.wordpress.com/2012/02/13/dont-store-that... Storing floating point coordinates for example is what causes the "farlands" world generation behavior in Minecraft, for example.