3 ms·

There's a related very nice article about the calculator in Android, by Hans-J. Boehm: https://cacm.acm.org/magazines/2017/8/219594-small-data-computing/fulltex

• lifthrasiir 7y ago
  Wow, this is better than I've ever expected: Android calculator makes use of Exact Real Arithmetic running in the background (with some tweaks to cope with the inherent undecidability and an infinite list of trailing zeros). I had been fully aware of ERA but never expected to see that in a such widespread application.
  • kerkeslager 7y ago
    This looks pretty interesting. Is there any good resource on this?
    • lifthrasiir 7y ago
      Searching for "Exact Real Arithmetic" will yield some. Specifically, a HaskellWiki page [1] is not too bad as a starting point. Or, if you are keen to academic presentations (read: presentations optimized for the maximal information density and not for the actual presentation ;-) [2] might be better. You can also take a look at the actual source code for the Android ExactCalculator app [3]. For some reason, however, it is deprecated after Android 9.0.0; don't know why. [1] https://wiki.haskell.org/Exact_real_arithmetic https://wiki.haskell.org/Exact_real_arithmetic [2] https://members.loria.fr/PZimmermann/irram18.pdf https://members.loria.fr/PZimmermann/irram18.pdf [3] https://android.googlesource.com/platform/packages/apps/ExactCalculator/+/refs/tags/android-9.0.0_r49/src/com/android/calculator2 https://android.googlesource.com/platform/packages/apps/Exac...
    • thechao 7y ago
      Hans Boehm has code: https://hboehm.info/new_crcalc/CR.java https://hboehm.info/new_crcalc/CR.java