Re: Data interpolation
- To: mathgroup at smc.vnet.net
- Subject: [mg96327] Re: Data interpolation
- From: dh <dh at metrohm.com>
- Date: Wed, 11 Feb 2009 05:24:49 -0500 (EST)
- References: <gmp11b$c6r$1@smc.vnet.net> <gmrm4r$9mr$1@smc.vnet.net>
Hi Sjoerd,
to my knowledge thats wrong. ListInterpolate can only interpolate data
on a grid. Otherwise, please give an example.
Daniel
Sjoerd C. de Vries wrote:
> hemanth,
>
> ListInterpolation will do what you want nicely.
>
> Cheers -- Sjoerd
>
> On Feb 9, 12:37 pm, hemanth korrapati <hemanthkorrap... at gmail.com>
> wrote:
>> Hi,
>>
>> I have some 3D point data acquired through a laser range finder. The
>> data is sparse. I need to construct a height field out of this data
>> and as a part of this i have to interpolate heights at some locations
>> {x,y} where the actual data is not available.
>> I want to use B-splines. But it seems that B-splines require uniformly
>> distributed control points, which is not the case with my data.
>> My data cannot form a uniform table which is required by the
>> BSplineSurface function if I sort my data.
>>
>> for some data i got the following error:
>> Interpolation::indim: The coordinates do not lie on a structured
>> tensor product grid. >>
>>
>> So I started using the "ListDensityPlot" function which does a linear
>> interpolation of the data. The interpolation is sufficiently good. But
>> I would like to get an output consisting of list of tuples like
>> {x,y,InterpolatedHeight} at the desired {x,y} locations. Right now I
>> can only see the plot but cannot get the interpolated heights at
>> desired locations({x,y}).
>>
>> Now I have three questions:
>> 1) how do i make my data usable for splines in mathematica ?
>> 2) how do i get the interpolated values at desired {x,y} using
>> "ListDensityPlot" function ?
>> 3) Is there a better way other than the above two methods to
>> interpolate the missing data ?
>>
>> Thank you
>
>