Re: [Bug-apl] Rational Numbers

[Juergen Sauermann]

Hi Elias, the format bug is fixed in SVN 983. Rational numbers are exact, they are stored as a 64 bit numerator and a 64 bit denominator. You can convert a rational to a float with monadic +:       ⎕PS←1 0   ⍝ display quotients       2÷3 2÷3       +2÷3 0.6666666667 Normally monadic + is not needed because conversion to double happens automatically where needed. /// Jürgen On 07/21/2017 06:19 AM, Elias Mårtenson wrote: There is an error in the rational code: In Archive.cc, line 218, the snprintf format is wrong. %lld is used, while the types of the arguments are actually "long". Thus, "%lld÷%lld" should be "%ld÷%ld" instead. On 21 July 2017 at 12:06, Elias Mårtenson <loke...@gmail.com> wrote: I haven't looked at this yet, but is this purely a display feature, or is it a full implementation of rational numbers? In other words, is the result of 1÷3 exact? And if so, how do I convert a rational number into a floating-point number? Regards, Elias On 21 July 2017 at 00:05, Juergen Sauermann <juergen.sauerm...@t-online.de> wrote: Hi, coming back to a proposal from Elias, I have added (experimental) support for rational numbers in GNU APL. SVN 982. It has to be enabled explicitly: ./configure RATIONAL_NUMBERS_WANTED=yes In APL you can display rational numbers by setting ⎕PS[1]:       ⎕PS←0 22       2÷3 ╔════════════╗ ║0.6666666667║ ╚════════════╝       ⎕PS←1 22       2÷3 ╔═══╗ ║2÷3║ ╚═══╝ (The second item in ⎕PS is a boxing style as in the ]BOXING command). Best Regards, Jürgen