Implementing a bignum calculator – Rob Pike [video]
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Re: Implementing a bignum calculator – Rob Pike [video]
#2Rob mentions a video demonstrating the development of an APL version of Conway's Game Of Life. Pretty sure it's this one if anyone is interested: http://youtu.be/a9xAKttWgP4
Re: Implementing a bignum calculator – Rob Pike [video]
#3Github repo:
Re: Implementing a bignum calculator – Rob Pike [video]
#4He wants to compute some bignums, so he writes an APL interpreter in Go...
Now he is scratching his itch and making nice slides to boot.
However, it would have been simpler for him to have typed "python" at the commandline... Python ints are arb precision :)
Re: Implementing a bignum calculator – Rob Pike [video]
#5He wants to compute some bignums, so he writes an APL interpreter in Go... Now he is scratching his itch and making nice slides to boot. However, it would have been simpler for him to have typed "python" at the commandline... Python ints are arb precision :)
> Python ints are arb precision
Python 2 longs or Python 3 ints ;)
Re: Implementing a bignum calculator – Rob Pike [video]
#6He wants to compute some bignums, so he writes an APL interpreter in Go... Now he is scratching his itch and making nice slides to boot. However, it would have been simpler for him to have typed "python" at the commandline... Python ints are arb precision :)
> Python ints are arb precision Python 2 longs or Python 3 ints ;)
Automatic promotion from a 32-bit or 64-bit storage to arbitrary precision.
Re: Implementing a bignum calculator – Rob Pike [video]
#7He wants to compute some bignums, so he writes an APL interpreter in Go... Now he is scratching his itch and making nice slides to boot. However, it would have been simpler for him to have typed "python" at the commandline... Python ints are arb precision :)
Lisp would be even better, as he would get the speed of compiled language.
Re: Implementing a bignum calculator – Rob Pike [video]
#8He wants to compute some bignums, so he writes an APL interpreter in Go... Now he is scratching his itch and making nice slides to boot. However, it would have been simpler for him to have typed "python" at the commandline... Python ints are arb precision :)
Arbitrary precision is handled by https://golang.org/pkg/math/big/
He isn't implementing a bignum package, this is all about the APL interpreter.
Re: Implementing a bignum calculator – Rob Pike [video]
#9He wants to compute some bignums, so he writes an APL interpreter in Go... Now he is scratching his itch and making nice slides to boot. However, it would have been simpler for him to have typed "python" at the commandline... Python ints are arb precision :)
Yes, but he wasn't trying to compute numbers. He was trying to build a calculator. There's a difference.
Re: Implementing a bignum calculator – Rob Pike [video]
#10He wants to compute some bignums, so he writes an APL interpreter in Go... Now he is scratching his itch and making nice slides to boot. However, it would have been simpler for him to have typed "python" at the commandline... Python ints are arb precision :)
or GNU CLISP which not only has big ints, big ratios, big complex (like all Common Lisp implementations), but also big floats.
Big ratios:
[2]> (/ 5723475972349572938475982734985723984759823749587 7239457928374598723984759237459723497598234)
5723475972349572938475982734985723984759823749587/7239457928374598723984759237459723497598234
[4]> (* 572934759237495723482374957239475982374957239847523485 (sqrt -1))
#C(0 572934759237495723482374957239475982374957239847523485)
[8]> (SETF (EXT:LONG-FLOAT-DIGITS) 1000)
1000
[9]> (sqrt 2.0l0)
1.4142135623730950488016887242096980785696718753769480731766797379907324784621070388503875343276415727350138462309122970249248360558507372126441214970999358314132226659275055927557999505011527820605714701095599716059702745345968620147285174186408891986095523292304843087143214508397626036279952514079896872534L0