similar to: interpolation and 3D plots

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

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'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")

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

Dear all, I'm trying to interpolate a dataset to give it twice as many values (I'm giving the dataset a finer resolution by interpolating from 1 degree to 0.5 degrees) to match that of a corresponding dataset. I have the data in both a data frame format (longitude column header values along the top with latitude row header values down the side) or column format (in the format latitude,

Dear all. I am using the akima function to produce 3d contour plots using interp based on irregular data. using the eg in the akima manual library("akima") data(akima) plot(y ~ x, data = akima, main = "akima example data") with(akima, text(x, y, formatC(z,dig=2), adj = -0.1)) ## linear interpolation akima.li <- interp(akima$x, akima$y, akima$z) image (akima.li, add=TRUE)

Readers, I have looked at various documents hosted on the web site; I couldn't find anything on interpolation. So I started r and accessed the help (help.start()). (by the way is it possible to configure r to open help in opera instead of firefox?) Initially I read the help for the akima package but couldn't understand it. Next I tried the asplines package help. I tried to copy the

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

The akima package has a problematic license (it doesn't allow commercial use), so it's been recommended that people use the interp package instead. When I use interp::interp instead of akima::interp, I get reasonable output from your example. So that's another reason to drop akima... Duncan Murdoch On 26/01/2023 9:35 a.m., PIKAL Petr wrote: > Dear all > > I have this

Dear all I have this table > dput(mat) mat <- structure(c(2, 16, 9, 2, 16, 1, 1, 4, 7, 7, 44.52, 42.8, 43.54, 40.26, 40.09), dim = c(5L, 3L)) And I want to calculate result for contour or image plots as I did few years ago. However interp does not compute the z values and gives me zeros in z matrix. library(akima) > interp(mat[,1], mat[,2], mat[, 3], nx=5, ny=5) $x [1] 2.0 5.5

What package/code could I use to create a 3-d surface graph of the predicted values over two of the explanatory variables' coefficients? Jim James Bang Department of Economics University of Illinois Well I AM missing the back of my head.you COULD cut me a little slack! -Homer Simpson

Hi everybody. i have 2 datasets : one with a long grid a lat grid and a bathymetry grid the second one only has the long and lat coordinates. So i want to know the bathymetry associated to the second dataset. I thought it was a good idea to do an interpolation between the two datasets. I find a script doing that on matlab but i want to do it on R. Do you how to do it? for ii =

Dear R users, I want to do a fitted.contour plot of selected columns of a dataframe M with M$AM and M$Irradiance as x and y axes respectively. The level of the contour shall be determined by M$PR. Some words on my data first. Dataframe M looks like: head(M$Irradiance) [1] 293 350 412 419 477 509 head(M$AM) [1] 2.407 2.161 1.964 1.805 1.673 1.563 head(M$PR) [1] 70.102 72.600 75.097 80.167

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

Dear All I hope that someone can help. I am working with sp pakage and akima library("akima") library(sp) imagine lots of different dataframes, of row = 100 columns = 3 of x and y coordinates with z values I will call these data frames for the sake of this example akima akima<-as.list(1:100) producing 100 dataframes dataframes of the form akima[[i]] I then wish to interp this

Dear all! I'm using R 2.12.1 in Ubuntu 10.04. Problem is that when using functions like interp (package akima) and akimaInterp (package fUtilities), I get different results every time for the same data set. I've checked the interpolated results, and two examples (in attachment) have different sum of NA values. Also when I subtract the x,y,z values from two interpolations of the same data

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

Hi How can I do the same has interp in s+ with R ? I've looked to "approxfun" but didn't figured out how to do it. Thanks EJ -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body",

hello, is it possible to do something like splinefun(x,y), but with a 3rd dim? for example, if i have a 2-dim system like: x<-1:100 y<-rexp(100,1) func<-splinefun(x,sort(y)) func(n) # returns interpolated value of y (after sorting) given x=n # i can check this by: plot(x,sort(y)) lines(spline(x,sort(y))) Can i do the same thing with an x,y, and z? i have found the akima

Dear All, I am trying to visualize the surface of a bivariate kernel density estimate. I have a vector of bivariate observations(x,y), and a function which computes the kernel density estimate z corresponding to each observation. I cannot generate the (x,y) data in the ascending order needed by persp(x,y,z). I was wondering whether there is an R version of the S function interp. Would anybody