Android is a Linux and I guess it is similar to the OLPC so I guess J will run on it
http://source.android.com/ Android is the first free, open source, and fully customizable mobile platform. http://androidlinux.com/ http://www.linux-netbook.com/ I am pretty sure J will run on this machine as well. It is an excellent opportunity to teach the kids to use J on these machines. I gave one to my daughter the other day. It took a while to discover how to open the terminal otherwise J installed and worked like a charm. 2009/5/4 David Vincent-Jones <[email protected]> > Don; before this well flogged subject dies away ... > > If children were introduces to J on their OLPC or similar notebooks at > the first grade level, with a dozen (or less) primary verb functions ... > then by the time they were ready to understand standard deviation, 'S' > would be an unnecessary branching out of J. > > David > > > On Fri, 2009-05-01 at 06:14 -0400, Don Watson wrote: > > Hi Ric, > > > > You wrote: > > > > > ''Let > > > mean=: (+/y) % #y > > > ssdev=: +/ *: y - mean y > > > var=: (ssdev y) % <:#y > > > stddev=: %: var y > > > ) > > > > Tacit J is a central component of J that is introduced early in the > > documentation All I really want is a mode in which I can remove the > > surrounding material and just write: > > > > mean=: (+/y) % #y > > ssdev=: +/ *: y - mean y > > var=: (ssdev y) % <:#y > > stddev=: %: var y > > stddev2=: %: (% <:#y) * +/ *: y - (+/y) % #y > > > > That's not a lot to ask. I'll give up on replacing the x and y with [ and > ]. > > > > Anyway, I have some work to do, I'll be back. > > > > Don > > > > ----- Original Message ----- > > From: "Sherlock, Ric" <[email protected]> > > To: "Chat forum" <[email protected]> > > Sent: Friday, May 01, 2009 3:25 AM > > Subject: Re: [Jchat] Language S > > > > > > > Don, > > > > > > So far the all the evidence and advice brought up in this thread > suggests > > > that: > > > * explicit reference to arguments in equations is likely to be less > > > confusing to math students (or beginning J users) than tacit or > > > implicit references. > > > * the use of a little additional syntax to define verbs presents > > > little or no barrier to students unfamiliar with J and/or > > > programming. > > > > > > I wonder at this point whether you would be receptive to going back to > an > > > earlier suggestion in post by Oleg proposing a "verb definition mode"? > > > > > > The implementation details are specified on the wiki page: > > > <http://www.jsoftware.com/jwiki/Phrases/Definitions> > > > > > > If the adverb "defn" on that page were renamed "Let" you could use it > in a > > > session like this: > > > > > > ============== > > > NB. blah blah intro > > > NB. For: > > > y=: 3 4 9 4 3 8 5 > > > NB. The mean is > > > (+/y) % #y > > > 4.6 > > > > > > NB. ... when want to define verbs: > > > > > > ''Let > > > mean=: (+/y) % #y > > > ssdev=: +/ *: y - mean y > > > var=: (ssdev y) % <:#y > > > stddev=: %: var y > > > ) > > > mean y > > > 4.6 > > > ssdev y > > > 29.2 > > > var y > > > 7.3 > > > stddev y > > > 2.70185 > > > > > > ================== > > > > > > If you wanted to get really picky you could define a noun > > > Now=: 'whatever you like cause it just gets ignored' > > > > > > So that you could write: > > > > > > Now Let > > > coeffvar=: (stddev y) % mean y > > > ) > > > > > > That's getting pretty close to the treatment of equations in a text > book? > > > > > > Note you are free to make the definition for stddev one big line if you > > > like, I just think that dividing it up into meaningful bits as above is > > > more illuminating (not to mention flexible). > > > > > > > > > ---------------------------------------------------------------------- > > > 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 > -- Björn Helgason, Verkfræðingur Fugl&Fiskur ehf, Þerneyjarsundi 23, Hraunborgum Po Box 127,801 Selfoss , t-póst: [email protected] gsm: +3546985532 Landslags og skrúðgarðagerð, gröfuþjónusta http://groups.google.com/group/J-Programming Tæknikunnátta höndlar hið flókna, sköpunargáfa er meistari einfaldleikans góður kennari getur stigið á tær án þess að glansinn fari af skónum /|_ .-----------------------------------. ,' .\ / | Með léttri lund verður | ,--' _,' | Dagurinn í dag | / / | Enn betri en gærdagurinn | ( -. | `-----------------------------------' | ) | (\_ _/) (`-. '--.) (='.'=) ♖♘♗♕♔♙ `. )----' (")_(") ☃☠ ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
