Re: Minimization
- To: mathgroup at smc.vnet.net
- Subject: [mg42275] Re: Minimization
- From: "Carl K. Woll" <carlw at u.washington.edu>
- Date: Thu, 26 Jun 2003 05:36:28 -0400 (EDT)
- Organization: University of Washington
- References: <bdbeu1$2dq$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
John,
Here is a version which is a bit faster on my machine than Hartmut's, where
I use pts instead of l1.
pts[[Ordering[Plus@@((Transpose[pts]-p0)^2),5]]]
The improvement in speed comes from using
Plus@@((Transpose[pts]-p0)^2)
instead of Hartmut's
With[{r=#-p0},r.r]&/@pts
Further improvements in speed may be achievable if you use Compile.
Carl Woll
Physics Dept
U of Washington
<Moranresearch at aol.com> wrote in message news:bdbeu1$2dq$1 at smc.vnet.net...
>
> I have a list of points l1= (xi,yi, zi) and a target point (x0,y0,z0) how
> would I efficiently find the 5 points in l1 closest to, ie with the
smallest
> Euclidian disance to, the target point? Thank you.
> John
>