Re: Problems to find the local extrema of an InterpolatingFunction
- To: mathgroup at smc.vnet.net
- Subject: [mg87902] Re: [mg87876] Problems to find the local extrema of an InterpolatingFunction
- From: "W_Craig Carter" <ccarter at mit.edu>
- Date: Sat, 19 Apr 2008 23:49:56 -0400 (EDT)
- References: <200804190734.DAA09779@smc.vnet.net>
Hello Modeler,
I beleive the best strategy for you is: plot your
InterpolationFunction over its
finite domain, visually look for the roots, and then find them with:
FindRoot[InterpolatingFunction[x],{x,firstguess,leftlimit, rightlimit}]
If you need to do this for many unknown Interpolating functions, then
you will need to automate this a bit---for example by moving the
search domain iteratively. But, if you only have one, graphically
assisted root finding works well in my experience.
Craig
On Sat, Apr 19, 2008 at 3:34 AM, Modeler <eabad at ulb.ac.be> wrote:
> Hi,
>
> does anyone know how to find all the local extrema of an InterpolatingFunction in a specified interval? The only
> thing that seems to work is Findroot, but it only finds a single root each time. Other rootfinding commands do not seem to work. Thanks for your help.
>
>
--
W. Craig Carter
- References:
- Problems to find the local extrema of an InterpolatingFunction
- From: Modeler <eabad@ulb.ac.be>
- Problems to find the local extrema of an InterpolatingFunction