Thanks again
From: Henry Rich <[email protected]> To: Programming forum <[email protected]> Sent: Monday, August 8, 2011 2:10 AM Subject: Re: [Jprogramming] value error Plot a list of vectors: 'color blue' plot (_2 ]\ 1 2 3 4 5 6) ; (_2 ]\ 3 1 4 1 5 9) Henry Rich On 8/8/2011 3:57 AM, nykkyo Kane wrote: > I got it working and found out "#" does the same thing, I have all I need > except how to plot multiple line segments (using plot) on the same graph. In > other words, how ro plot a vector field on a plane. > > Thanks again. > > From: mijj<[email protected]> > To: Programming forum<[email protected]> > Sent: Monday, August 8, 2011 12:22 AM > Subject: Re: [Jprogramming] value error > > hi Mr Kane.. > > from a novice perspective (having come from those pitfalls only > recently) i notice (as well as the assignment lapse, which i continjue > to do all the time) 2 errors in the use of :[ return ]: > > i.e... > :[ return t ]: should actually be :[ t return. ]: for it to work as i'm > guessing you expect (returning the value "t"?). > > First problem... missing :[ . ]: from the end of "return". > > Second... :[ return. t ]: wouldn't return the value "t" after it. It > would quit immediately returning the most recent expressed value > *before* the return. So, if you want to return the value "t" ... :[ t > return. ]: > > ........ > (nb.^:1) i like to use :[ return. ]: as an explicit marker to help with > cursory examination of a construction. I don't know if a superfluous :[ > return. ]: has a performance penalty, but until i create something where > it makes a difference, i find it useful. > > > (nb.^:2) i'm toying with using :[ ... ]: in emails to isolate bits of J > within text to make it stand out. I've not decided yet if it looks too > silly to continue using.) > > > On 2011-08-08 03:56, nykkyo Kane wrote: >> Following is a creenshot of my "J" console. I do not understand why I am >> getting a error> >> ================= >> compress 4 : 0 >> i =. 0 >> t =. 0$0 >> while. i< $x do. >> if. 1 = i{x do. t =. t , i{y end. >> i =.>:i >> end. >> return t >> ) >> >> compress 4 : 0 >> i =. 0 >> t =. 0$0 >> while. i< $x do. >> if. 1 = i{x do. t =. t , i{y end. >> i =.>:i >> end. >> return t >> ) >> b compress a >> |value error: compress >> | b compress a >> a >> 11 12 13 14 15 16 17 18 19 20 >> b >> 1 0 1 0 1 0 1 0 1 0 >> ---------------------------------------------------------------------- >> 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 ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
