" (0&^) d. _1 gives a domain error. Possibly this is unwanted, I mean, it could be considered as a constant since 0^x = 1 in usual understanding, but Wolfram Alpha also has issues with this: https://www.wolframalpha.com/input/?i=integrate+0%5Ex "
Right, J, among several other programming languages, regards 0^0 as 1. Wolfram Alpha and some programming languages regard 0^0 as undefined: https://www.wolframalpha.com/input/?i=0%5E0 On Sun, Oct 1, 2017 at 10:42 AM, 'Jon Hough' via Source < sou...@jsoftware.com> wrote: > I have made a couple of minor edits and added some comments, and J syntax: > https://github.com/jonghough/jsource/blob/master/jsrc/cd.c LINES 281 - > 301 > > A couple of points. > > (0&^) d. _1 gives a domain error. Possibly this is unwanted, I mean, it > could be considered as a constant since 0^x = 1 in usual understanding, but > Wolfram Alpha also has issues with this: > https://www.wolframalpha.com/input/?i=integrate+0%5Ex > > Negative bases for exponentials give complex results. This is > mathematically correct, but thought I would mention it anyway. > e.g. > (_2&^) d. _1 > %&0.693147180559945286j3.14159265358979312@(_2&^) NB. correct > see: https://www.wolframalpha.com/input/?i=integrate+(-2)%5Ex > > Compare this to current J, where > (_2&^) d. _1 > gives a domain error. > -------------------------------------------- > On Fri, 9/29/17, 'Jon Hough' via Source <sou...@jsoftware.com> wrote: > > Subject: Re: [Jsource] d. fix > To: sou...@jsoftware.com > Date: Friday, September 29, 2017, 12:15 PM > > Sorry Henry, > > I somehow missed this email in my > inbox. > > I will get the fixes you need done this > weekend. > > Regards, > Jon > > -------------------------------------------- > On Mon, 9/25/17, Henry Rich <henryhr...@gmail.com> > wrote: > > Subject: [Jsource] d. fix > To: "'Jon Hough' via Source" <sou...@jsoftware.com> > Date: Monday, September 25, 2017, 1:06 > AM > > John, > > I finally have my PC back and > would > like to get your fix in before > the next build, which is happening > any > day now. However, I have issues > with it: > > 1. Needs commentary. The JE didn't > have much to begin with & that > needs > to improve. So at least put in > enough > commentary that a reader can tell > what you are doing without reading > the > C code. I put in an average of > about one line of comment for each > line > of C. As it stands it will me > more time than I care to spend to > verify that what you are doing is > valid. > > As part of the commentary, translate > those long calls [amp(ds(CDIV...] to > J. > > 2. AT(x)==INT is no good, because > there > may be flags set in more > significant bits of the type. Use > (AT(x)&INT) > > When you respond, send me your new > testcase (gddot, I think) and point > me to the fix, perhaps by simply > sending me the new cd.c. > > hhr > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
