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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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>* -- 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/CALoEmQzxi4o35ONtqpdJyQQy%3DCd3Zt_JU6k0dTGCCsnMDrWCkw%40mail.gmail.com.
