forgot the code...final test is what generates the report above. float128.go: https://play.golang.org/p/2MzjllLC3qT float128_test.go: https://play.golang.org/p/ZQwsFh0_Apt
On Sat, Feb 1, 2020 at 7:32 PM Michael Jones <michael.jo...@gmail.com> wrote: > As promised, some careful results from one of the tests in my > doubled-precision library. > > Rows are iteration's of Jean-Michel Muller's roundoff-intolerant Œ() > function: > > http://perso.ens-lyon.fr/jean-michel.muller/ > > Columns are 32-bit floating point,64-bit floating point, my fast 128-bit > library, Go big float, and Go rationals (printed as float) > > Answers are good for a while, and then fail as they must. compare always > to the right column. > > Also, Dr. Kahan on the topic -- always read his every word! > > How Futile are Mindless Assessments of Roundoff In Floating-Point > Computation ? > Professor W. Kahan > § 5, page 14 > https://www.cs.berkeley.edu/~wkahan/Mindless.pdf > > > === RUN TestMuller > 0: 4.000000000 4.000000000000000000 > +4.0000000000000000000000000000000e+00 4.0000000000000000000000000000000 > 4.0000000000000000000000000000000000000000000000000000000000000000000000… > 1: 4.250000000 4.250000000000000000 > +4.2500000000000000000000000000000e+00 4.2500000000000000000000000000000 > 4.2500000000000000000000000000000000000000000000000000000000000000000000… > 2: 4.470588684 4.470588235294115975 > +4.4705882352941176470588235294117e+00 4.4705882352941176470588235294118 > 4.4705882352941176470588235294117647058823529411764705882352941176470588… > 3: 4.644744873 4.644736842105217534 > +4.6447368421052631578947368421047e+00 4.6447368421052631578947368421053 > 4.6447368421052631578947368421052631578947368421052631578947368421052632… > 4: 4.770706177 4.770538243625082941 > +4.7705382436260623229461756373816e+00 4.7705382436260623229461756373938 > 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4.9999999999999999999997822271254999763646344602901264147280098852591988… > --- PASS: TestMuller (0.00s) > PASS > ok float128 0.011s > > Be thoughtful in numerical computation. > > Michael > > On Sat, Feb 1, 2020 at 5:54 PM Jason E. Aten <j.e.a...@gmail.com> wrote: > >> I appreciate the sophisticated and math conscious discussion here. >> >> For those reading this thread in the future, I note the state of the art >> in Go at the moment seems to be this >> arbitrary precision decimal library created by the CockroachDB guys for >> APD standard/postgresql conformance. >> Note that arbitrary doesn't mean infinite, it means you can pick the >> precision your application needs. >> >> https://github.com/cockroachdb/apd >> >> -- >> You received this message because you are subscribed to the Google Groups >> "golang-nuts" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to golang-nuts+unsubscr...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/golang-nuts/dde824b9-f200-43df-8461-1d5fc26c1cce%40googlegroups.com >> <https://groups.google.com/d/msgid/golang-nuts/dde824b9-f200-43df-8461-1d5fc26c1cce%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > > > -- > > *Michael T. jonesmichael.jo...@gmail.com <michael.jo...@gmail.com>* > -- *Michael T. jonesmichael.jo...@gmail.com <michael.jo...@gmail.com>* -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/CALoEmQya0f7k-fP-drRNxTFfAO-DSfEUm_BqJxSS_v1tu%3DKERg%40mail.gmail.com.
