If you add support for this to Julia, I want to make sure I can add the format to my own record storage format efficiently. (This sounds great!)
On Sunday, July 26, 2015 at 9:09:19 AM UTC-4, Tom Breloff wrote: > > Unums as a general concept seem really interesting. I ordered the book, > and may start a julia implementation (unless someone else gets there > first). Unified integer and floating point with clear accuracy information > could provide nice solutions for certain problems in finance and > statistics. For example, I have a specialized solution to represent > financial prices which have a fixed accuracy, but I want to be able to do > floating point arithmetic on them. This requires lots of converting between > int and float, rounding, etc. Unums may completely change those operations. > > If anyone starts an implementation, please post the package link here so > we don't duplicate efforts. > > On Sunday, July 26, 2015, Scott Jones <[email protected] <javascript:>> > wrote: > >> >> >> On Sunday, July 26, 2015 at 7:51:51 AM UTC-4, Job van der Zwan wrote: >>> >>> So on an impulse I got the ebook, and even for a physics dropout like me >>> it's surprisingly engaging and accessible! There's some stuff in there that >>> isn't mentioned in the online slides that might clarify the idea better. >>> >>> For example, floats already have a way to represent the largest >>> representable number (maxreal) and positive infinity. Add a ubit gives you >>> the following: >>> >>> - maxreal without ubit: largest rep. number >>> - maxreal with ubit: interval between maxreal and infinity >>> - infinity without ubit: infinity >>> - infinity with ubit: the interval between... infinity and beyond? >>> >>> So what that gives you is a way to represent a number that is bigger >>> than what you can represent, but not infinite (maxreal + ubit), and NaN >>> (infinity + ubit). For negative numbers, just add sign bit. >>> >>> On Sunday, 26 July 2015 13:59:33 UTC+3, Scott Jones wrote: >>>> >>>> Yes, but I could add the information about "inexact" vs. "exact" and >>>> keeping track of significant figures to my format as well, while still >>>> storing many common values in just 1 byte (including Null, "", and markers >>>> for binary and packed Unicode text). >>> >>> >>> Well, at the very least it seems to inspire some ways you might improve >>> your format! :) >>> >> >> Yes, and I am interested in hearing about hardware support for the UNUM >> format. >> I'm also curious about how these ideas interact with decimal floating >> point (which is what I'm more familiar with, because for the sorts of >> operations important for the use cases I was concerned with, not having >> rounding/conversion issues between decimal <-> binary floating point or >> string <-> binary floating point was critical). >> >>
