Look up the value "undefined" in te J dictionary.
And then program so as to avoid placing any other meaning on it. Thus, whenever you encounter it in a J computation, it would indicate your failure to program properly. And provide an immediate fence post to wht I call eigenstate collape: Your program has no proper meaning at that point relativ to your original attempted solution. More importantly, make sure that every computation made strays fully _within_ all relevant bounds (size, null vectors, unasigned values, over- and under-flow AS WELL AS other numerical analysis failures, not too uch and not too little randomness if involved, and so on). Only the _implementor_ can ascertain and attempt to denote failures of these constraints, and only the implementor has a chance to actually ASSIGN an "undefined" value if these bounds are transgressed. The same philosophy already exists in J's design, which is why so many o fthese errors are inherently avoided: because it is just that much harder to MAKE uch an error in J. Because J tends to _correctly_ implment _Mathematocs_ correctly so much more of the time. BUT not all if the time, and cetainly J cannot maintain the _inent_ a program is intended to obey by its mplementor. THAT has to be done by the programmer. By specific conscious ongoingh effort at maintaing the intent to _correctly_ keep the purpose of the program intact at all times. Very hard to do in any non-simple program. Hrd enough even in the simple ones. On 6/20/06, dly <[EMAIL PROTECTED]> wrote:
By undefined in J do you mean a variable to which no value has been assigned? an attribute that is defined for some but not all? is it associated with something like null which you can test for? how does J handle the undefined? Donna [EMAIL PROTECTED] On 20-Jun-06, at 9:51 PM, dly wrote: > For the beginner in J > > can you point me to a help reference to the undefined in J ? > > Re: Schroedinger's Qat--and I always thought he was talking about a > cat--this puts things in entirely new purple haze. > > Donna > [EMAIL PROTECTED] > > > > On 20-Jun-06, at 9:30 PM, Roy A. Crabtree wrote: > >> which is why the undefined value in J is so important. >> >> It corresponds roughly to the Aisan concept of yes, no, _mu_: > >> Schroedinger's Qat being neither dead nor alive until someone >> looks to see. >> > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
-- -- Roy A. Crabtree UNC '76 gaa.lifer#11086 Room 207 Studio Plus 123 East McCullough Drive Charlotte, NC 28262-3306 336-340-1304 (office/home/cell/vmail) 704-510-0108x7404 (voicemail residence) [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] http://www.authorsden.com/royacrabtree http://skyscraper.fortunecity.com/activex/720/resume/full.doc -- (c) RAC/IP, ARE,PRO,PAST (Copyright) Roy Andrew Crabtree/In Perpetuity All Rights/Reserved Explicitly Public Reuse Only Profits Always Safe Traded ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
