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Re: smooth kdensity

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Karl wrote:

> Am 22.06.2013 02:48, schrieb sfeam:
>> Karl wrote:
>> 
>>> And i saw that the possibility to give an explicit kernel width for
>>> every data point in a third column has been removed in CVS. For
>>> example for scattering experiments, the kernel should be larger for
>>> smaller 2theta values, because the resolution of a linear detector
>>> is smaller there.
>> 
>> My understanding is that bandwidth is a property of all the points
>> jointly, so it would make no sense to have a different bandwidth
>> for each point.  Do you have a reference that discusses the use
>> of a non-constant bandwidth?
>> 
> I´ll have to dig for some reference, tell you when i have one.
> 
> One thing is that in a diffraction pattern with several peaks, each
> can have it´s idividual lineshape. 

By "lineshape" do you mean the rocking (Darwin) curve?
Below you are talking about detector nonlinearity, but here I'm not
sure whether you are talking about a property of the source, the
sample, or what.

> But then i think they would have to
> be handled (smoothed) individually, anyway.
> 
> But when the scattered points positions are not evenly distributed (as
> is the case if you measure angles with a linear or planar detector
> array), then the larger points should clearly get a proportionally
> higher bandwidth, i´d say.

I'm not sure about that.  In that case isn't the proper approach to
describe the non-linearity of the axis explicitly, and do your smoothing
or other analysis on the corrected coordinates?  It's going to be
necessary to work back to angular coordinates in any case in order to
interpret the peak locations.

	Ethan

> 
>  Karl

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smooth kdensity Karl <mail.kfr@gmx.net> - 2013-06-20 15:05 +0200
  Re: smooth kdensity sfeam <sfeam@users.sourceforge.net> - 2013-06-20 08:28 -0700
    Re: smooth kdensity Karl <mail.kfr@gmx.net> - 2013-06-20 20:09 +0200
      Re: smooth kdensity sfeam <sfeam@users.sourceforge.net> - 2013-06-21 17:48 -0700
        Re: smooth kdensity Karl <mail.kfr@gmx.net> - 2013-06-22 16:34 +0200
          Re: smooth kdensity sfeam <sfeam@users.sourceforge.net> - 2013-06-22 12:48 -0700
            Re: smooth kdensity Karl <mail.kfr@gmx.net> - 2013-06-24 06:12 +0200
              Re: smooth kdensity sfeam <sfeam@users.sourceforge.net> - 2013-06-28 12:09 -0700

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