Re: [R] Applying interpolation within a convex hull

Thank Rolf, I am aware of the extrapolation possibilities within the interpolation packages within akima but this interpolation often leads to unrealistic results for my sedimentary units. Therefore I would like to be able to just apply the interpolation to the thickness measurements within the c

[R] Applying interpolation within a convex hull

Hi there, I have been using the Tps function (within the Fields package) for a while now to interpolate different sedimentary units. Due to the method of formation of the units I know that at some edges the thickness of the unit decreases to zero. I was wondering if there was someway to specify t

Re: [R] Identifying nearest topographic contours to data points

Hi Rolf, Thanks for the feedback, I am indeed using the 'spatstat' package and now have the info I need. Thanks again, Sam -- View this message in context: http://r.789695.n4.nabble.com/Idetntifying-nearest-topographic-contours-to-data-points-tp3452462p3454680.html Sent from the R help mailing l

[R] Idetntifying nearest topographic contours to data points

Hi there, I have two data sets, one of locations at different elevations (x,y,z) and the other of points that make up topographic contours (also x,y,z). I have used: result<-apply(distppll(data2,cbind(topocon[-nrow(topocon),],topocon[-1,])),1,min) where 'data2' are my measurement coordinates (x,

[R] Finding functions of large dataset for numerical integration

Hello everyone, I have been trying to figure out away to integrate under a spline produced by the package tps(fields). As the package does not output functions I am trying to do something similar to the trapezium rule. My data are 3D (x, y & z). I have extracted from the surface output by Tps the

[R] Minus values in Tps

Hello there, I am using the Tps function to fit a spline to my data which is measurements of a sedimentary layer on an xy plane to see how the thickness of the layer changes. I was wondering if it was possible to change the Tps code so that no minus values are calculated by the spline as these a

[R] Integration under Tps

Hi there, After many attempts at trying different methods I have used the Tps package to interpolate between a number of measurements of field data, in this case thickness of a sedimentary deposit. My input values are Longitude, Latitude and Thickness and I have produced a valid contour map base

Re: [R] Splines under tension

Thank you for the helpful direction to the smoothing splines function, it was very helpful and is exactly what i am trying to do. My data however is 3-D, i.e. i have x and y values which are coordinates for different field sites and z values which are really what I am interested in analysing with

[R] Splines under tension

Does anyone know if R has a function for splines under tension. I know there are numerous packages for spline interpolation within R i just can't find one that lets you determine the tension factor. Any help would be much appreciated! Sam -- View this message in context: http://r.789695.n4.nab