similar to: interpolation to abscissa

== Summary == * Problem: BibTeX entries extracted from R packages via citation() require too much manual editing to be of general use. * Proposal: Date: fields should be made mandatory in package DESCRIPTION files, perhaps beginning with warnings from R CMD check * Proposal: Package authors should be encouraged to use a (new) Contributors: field in the DESCRIPTION file rather than packing all

Hello, I have a x,y,z file.Z is not corresponding to a simple analytical function of x and y (see below). I am trying to find the minimum location of this surface and the z value corresponding to this location by a spline interpolation or from a polynomial fit. I tried with the akima package but as the location of the point I am looking for (the minimum) is outside of the convex hull it's

Hi. I'm trying to take a data set with two independent and one dependent variable and enter a x,y value to predict the dependent with a nonparametric technique. I've been using interpp in the akima package, (windows xp, R 2.4.1), but get values that are orders of magnitude off when the predictors are slightly out of the range of the data set. Can you recommend a function for me?

Hello, Is there any other bivariate pointwise interpolation command besides akima's interpp? I tried to search through the J. Baron's page without luck. The problem is that I have got regularly spaced data (in x and y) what is not acceptable for interpp. I am not very much interested in the method of interpolation as the data are dense and the error would not be to high. Thanks in

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 that the interpolation only occurs within the convex hull of the data, outside of which the the values

Dear all; First of all, this is probably a more conceptual question than a R-related one, but still want to give it a try. When working with the interpolation function "interp" from the package akima and the triangulation function "tri.mesh" from package tripack I've got NA's for the interpolation and "error" for the triangulation. The data is arranged in a

Hi, I'm currently hunting a bug in the akima library, especially in the code behind the interpp.old function (bi-variate linear interpolation). It is based on a triangulation algorithm, interpolation at a given point needs to know the triangle which contains this point, then the interpolation is a straightforward calculation based on the three vertexes. The problem is: Sometimes the triangle

Hi everyone I was using spline to interpolate single or two consecutive missing data points in time series. However, when it comes to longer gaps in the data the spline function generate new data for both my known and unknown data (see below). Aside from not understanding why this happens, I thought thought I might try function "aspline" in library (akima). However, I cannot install or

Is it easy or difficult to label the abscissa of a scatter graph as 1/trueScaleValue at that point? -- View this message in context: http://r.789695.n4.nabble.com/labeling-abscissa-using-a-function-of-the-plotted-scale-tp4678075.html Sent from the R help mailing list archive at Nabble.com.

Hi all. I have defined a plot thus: par(mar=c(5,5,4,5),las=1, xpd=NA) plot(Day, Ym1Imp, ylim=c(0,100), type="b", bty="l", main="Ym1 Expression", cex=1.3, xaxt="n", yaxt="n") #plot implant data axis(side=1, at=c(0,1,3,5,7,10,14,21), labels=c(0,1,3,5,7,10,14,21)) # label x axis mtext("Day", side =1, at=10, line=3, cex=1.2) # title x

Hi, I'm trying to determine if R is useful to me. I've browsed 'The Basics of S and S-Plus' (Krause & Olson), and like the logic of the language. However, I don't see an easy way to do things like this: * given a set of observations (x,y) (x and y equal-length vectors), and a 2nd set of abscissas x2, interpolate y at the new abscissas x2. (for now, I don't really

Dear all, I am just wondering if anybody has implemented a function that can give a piecewise linear interpolation in more than 2 dimensions? I have looked at the akima package, but I would rather like a piecewise linear interpolation rather than a spline and while it did the job quite satisfactory for 2 dimensions, I need to interpolate in at least three dimensions. If anybody has implemented

Hello again, There is any package which does Z aware (real 3D) interpolations? It can be any method (IDW, kriging or spline) but it should take into consideration not only x and y coordinates for interpolation, but also z coordinate. I looked into different packages but it seems i didn't find the right one. The ultimate goal is to import the output into a GIS (Geographical Information

Hello all, I'm very new to R and am having some trouble with the results of the interp function. I'm trying to produce a chart roughly akin to a weather map with natural looking filled contours over a large region of the south pacific. I've got a list of points and values to be mapped to those points and I use the interp function as follows: tab<-read.table("data.txt")

Full_Name: Jonathan Lees Version: 2.0.1 OS: linux-gnu Submission from: (NULL) (152.2.75.65) there is a problem with calculating the convex hull in 2-D interpolation using the codes interp fromt eh akima package: x =c(0.6505304, -1.1821562, -0.2600792, 0.7913716) y = c(1.0424226, 0.1754048, -1.4523334, 0.2349112) z = c(0.000, 3.042, 0.370, 0.122) EX = seq(from=min(x), to=max(x),

Hello all, I want to interpolate some data i prepared in GRASS, so I'm looking for what interpolation methods are available for R. In GRASS I can do Splines with tension and IDW. I'm looking for something like multiquadric equations. Is there any function/package available fo rthis? thanks all -- +-------------------------------------------------+ Carlos Henrique Grohmann de

Dear All, I would like to plot a scalar (e.g. a temperature) on a non-rectangular domain (or even better: I would simply like to be able to draw a contour plot on an arbitrary 2D domain). I wonder if there is any tool to achieve that with R. I did some online search in particular on the list archives, found several queries similar to this one but was not able to find any conclusive answer. I

Hi, I am hired to translate into FORTRAN R functions. It works great and my customer is happy. I am going to translate a function that call aspline in the library AKIMA. This function call 2 FORTRAN routines that must be include (I guess) in the package AKIMA. And I have some questions. Is the fortran code really included in the R package AKIMA ? In other word, do I have a mean to call these 2

Dear Help List, My name is Matt Oliver. I have been using R for about a year and find it very helpful. However, I have a need for a function that I cannot find. I am not very good at programming so I thought I would ask the group. I have an irregular grid of data (x = Longitude, y = Latitude). Each pair of my x,y has a categorical value. Obviously linear or any other numerically based

Hi, I have three matrices (X,Y,P) with the same dimension. The X,Y grid is regular and I want to perform linear interpolation to pick out certain points. In matlab appropriate call is something like Pout=interp2(X,Y,P,Xout,Yout, method="linear") where Xout and Yout are the locations where I want the Pout data (typically a different grid). (Scipy has this routine in