Use an adverb: G =: 1 : '^@:(m&*)' _2 1 G ^@:(_2 1&*)
--Kip Murray On Sunday, March 15, 2015, Jon Hough <[email protected]> wrote: > Kip, Raul,Thanks for replying. > The matrix way would probably be better. > As a follow up question, I am having trouble creating an > adverb/conjunction to build solutions from. > if I define the conjunction > > F =: 2 : '^@:(n&*)' > > > and I give, as my noun argument, the solutions to some polynomial (e.g. > >1{ p. _2 1 1) > > Then I need to do > > '' F _2 1 > > > > > ^@:(_2 1&*) NB. the two solutions (without constants) > > > > > Which gives me my verb "solution". Please note that I had to give '' as > the left argument to F to return my verb. > > > Is there some other way of doing this? > i.e. I want some "part of speech" (conjunction or adverb I suppose) that > takes > a noun and returns a verb. > > > It seems conjunctions take verbs and nouns and return verbs > > > Conj: V x N --> V > > > but since, in my case for F, the verb is superfluous, is there any "part > of speech" that takes a noun and returns a verb? > > > I hope my question made sense. My motivation is, I don't see why I should > need to pass an empty verb '' to F to > return a verb. I only want to give F my noun and from that, I want to get > a verb. > > > Regards, > Jon > > > > > From: [email protected] <javascript:;> > > Date: Sun, 15 Mar 2015 14:46:35 -0400 > > To: [email protected] <javascript:;> > > Subject: Re: [Jprogramming] Solving Differential Eqns with J > > > > Oops, I should have seen that. > > > > Thanks, > > > > -- > > Raul > > > > On Sun, Mar 15, 2015 at 2:45 PM, Kip Murray <[email protected] > <javascript:;>> wrote: > > > Raul, where you have _1 * y you need _2 * y > > > > > > --Kip > > > > > > On Sunday, March 15, 2015, Raul Miller <[email protected] > <javascript:;>> wrote: > > > > > >> On Sat, Mar 14, 2015 at 7:11 AM, Kip Murray <[email protected] > <javascript:;> > > >> <javascript:;>> wrote: > > >> > I recommend a matrix approach involving eigenvalues and > eigenvectors, > > >> > and assume you have a way to find eigenvalues and eigenvectors for > an n > > >> by > > >> > n matrix which has n linearly independent eigenvectors. I confine > my > > >> > attention to linear differential equations with constant > coefficients and > > >> > right hand side 0, for example > > >> > > > >> > u''' - u'' - 4 u' + 4 u = 0 with initial conditions u(0) = 2 , > u'(0) = > > >> _1 > > >> > , and u''(0) = 5 > > >> > > > >> > This has the solution u(t) = ( ^ _2 * t ) + ( ^ t ) where I use > a mix > > >> of > > >> > conventional and J notation. > > >> > > >> I decided to try converting your notes here to J, and I ran into a > snag. > > >> > > >> First, I tried expressing your initial constraints in J: > > >> > > >> constraint=: 1 :0 > > >> if. 0 = y do. > > >> assert. 2 = u y > > >> assert. _1 = u D. 1 y > > >> assert. 5 = u D. 2 y > > >> end. > > >> assert. 0= (u D.3 + (_1*u D.2) + (_4 * u D. 1) + 4 * u) y > > >> ) > > >> > > >> And then I expressed your solution in J: > > >> > > >> solution=:3 :0 > > >> (^ _1 * y) + ^ y > > >> ) > > >> > > >> Or, alternatively: > > >> > > >> tacitsolution=: +&^ - > > >> > > >> And then I tested my code to see if I had gotten it right: > > >> > > >> solution constraint 0 > > >> |assertion failure > > >> | _1=u D.1 y > > >> > > >> Looking at this: > > >> solution D.1 (0) > > >> 9.76996e_8 > > >> tacitsolution D.1 (0) > > >> 9.76996e_8 > > >> > > >> working this through manually, > > >> > > >> dsolution=: 3 :0 > > >> (_1 * ^ _1*y) + ^ y > > >> ) > > >> > > >> dsolution 0 > > >> 0 > > >> > > >> So J's implementation of D. isn't perfect, but I'm wondering if you > > >> might not also have a typo somewhere in your presentation here? > > >> > > >> Thanks, > > >> > > >> -- > > >> Raul > > >> ---------------------------------------------------------------------- > > >> For information about J forums see > http://www.jsoftware.com/forums.htm > > >> > > > > > > > > > -- > > > Sent from Gmail Mobile > > > ---------------------------------------------------------------------- > > > 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 > -- Sent from Gmail Mobile ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
