Re: How do I get a DSolve'd function

*To*: mathgroup at smc.vnet.net*Subject*: [mg54440] Re: [mg54384] How do I get a DSolve'd function*From*: Chris Chiasson <chris.chiasson at gmail.com>*Date*: Sun, 20 Feb 2005 00:10:22 -0500 (EST)*References*: <200502190733.CAA06184@smc.vnet.net>*Reply-to*: Chris Chiasson <chris.chiasson at gmail.com>*Sender*: owner-wri-mathgroup at wolfram.com

This will work for your purposes: Block[{f = dummyfunction}, sol = DSolve[{f'[x] == -3f[x], f[0] == 10}, f, x]] f = dummyfunction /. sol[[1]] Plot[f[x], {x, 0, 10}] Regards, On Sat, 19 Feb 2005 02:33:01 -0500 (EST), Skirmantas <skirmantas.janusonis at yale.edu> wrote: > I hope this is the last question for now. > > I can solve a differential equation and plot it by doing something > like this: > > sol=DSolve[{f'[x]==-3f[x],f[0]==10},f,x] > Plot[f/.sol,{x,0,10}] > > But how do I get the function f[x] itself? I want to be able to input > f[x] and get its definition. Or do Plot[f[x],{x,0,10}]. Or define > y[x_]:=f[x]^2. > > f[x]/.sol or f[x_]:=f[x]/.sol or f[x_]:=sol[[n,n,n]] do not work. > > What if the solution is a function with many variables, say u[x,y,z]? > What's the correct way to "get" it? > > -- Chris Chiasson Kettering University Mechanical Engineering Graduate Student 1 810 265 3161

**References**:**How do I get a DSolve'd function***From:*skirmantas.janusonis@yale.edu (Skirmantas)