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Re: Nearest neighbours of points

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On 24/10/2015 23:44, Poul Riis wrote:

> def calc_dist(p1,p2):
>      return math.sqrt((p2[0] - p1[0]) ** 2 +
>                       (p2[1] - p1[1]) ** 2 +
>                       (p2[2] - p1[2]) ** 2)

>          dist=calc_dist(pts[i],pts[j])
>          if n==0:
>              distold=dist
>          else:
>              if dist <distold:

Just to compare two distances, you can probably work with the squares. 
You don't need the square root in calc_dist.

You will need it for the final report, but that's only one square root, 
not thousands or millions.

-- 
Bartc

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Nearest neighbours of points Poul Riis <priisdk@gmail.com> - 2015-10-24 13:05 -0700
  Re: Nearest neighbours of points Christian Gollwitzer <auriocus@gmx.de> - 2015-10-24 22:45 +0200
  Re: Nearest neighbours of points Poul Riis <priisdk@gmail.com> - 2015-10-24 15:44 -0700
    Re: Nearest neighbours of points Christian Gollwitzer <auriocus@gmx.de> - 2015-10-25 09:55 +0100
      Re: Nearest neighbours of points Poul Riis <priisdk@gmail.com> - 2015-10-25 05:00 -0700
      Re: Nearest neighbours of points Peter Pearson <pkpearson@nowhere.invalid> - 2015-10-25 17:01 +0000
    Re: Nearest neighbours of points Bartc <bc@freeuk.com> - 2015-10-25 12:36 +0000
  Re: Nearest neighbours of points Fabien <fabien.maussion@gmail.com> - 2015-10-26 03:25 +0100
  Re: Nearest neighbours of points Tom P <werotizy@freent.dd> - 2015-10-31 22:28 +0100
    Re: Nearest neighbours of points Terry Reedy <tjreedy@udel.edu> - 2015-10-31 23:00 -0400

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