Re: How to use the max value from the solution of NDSolve ?
- To: mathgroup at smc.vnet.net
- Subject: [mg72213] Re: How to use the max value from the solution of NDSolve ?
- From: dh <dh at metrohm.ch>
- Date: Thu, 14 Dec 2006 05:49:43 -0500 (EST)
- Organization: hispeed.ch
- References: <elosjf$on7$1@smc.vnet.net>
Hi Cham,
the output of NDSolve is an expression and parts of an expression may be
accessed by Part. E.g.:
sol = NDSolve[{x'[t] == x[t], x[0] == 3.4}, {x}, {t, 0, 10}];
sol[[1, 1, 2, 1, 1, 2]]
give the x-max.
Daniel
Cham wrote:
> Suppose I'm solving a differential equation with NDSolve :
>
> NDSolve[{ x'[t] == f[ x[t] ], x[0] == 3.4 ], { x }, {t, 0, 10}]
>
> Mathematica then finds a solution like this :
>
> Out[]= {{ x -> InterpolatingFunction[{{ 0., 2.6532}}, <>}}
>
> Next, I need to make several graphs of the solution. How can I point to the max value t = 2.6532 without retyping that value each time, especially if I change the initial condition x[0] == 3.4 and redo NDSolve again ? What is the name of the t_max found by Mathematica ? Or how can I point to that special value ? Is there a way ?
>