[R] How to create multi variables
Hi, everyone I want to create a series of variables (e.g. t1, t2..., t10) which could be used in loops. My idea is to use function assign for (i in 1:10) { assign(paste(t,i,sep=), FUN) # allocate the value from FUN to variable ti } But when I create a vector containing the names of these variables and want to use the variables according to the subscript, it doesn't works. t-noquote(paste(t,1:10,sep=)) t[1] t1 it returns only the name of variable t1, but not the value allocated to t1 by FUN. So what should I do to realize this? Or is there any better way to do this? Can we define a series of variables which can be used according to the subscript like t-f(t1, t2..., t10), then we have 10 variables which can be used directly? for(i in 1:10) { t[i]-FUN# with the fines variables we can directly assign the value of FUN to ti } These are just my thoughts, I don't know whether there are available R codes to realized it. I am looking forward any help from you. Thanks in advance! Yuanzhi __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
[R] regular pentagon
Hello, everyone, Do you have any idea to get a set of random points within a regular pentagon? Thanks in advance! Yuanzhi __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
[R] subset of data frame
Hi, everyone I met a small problem when I want take a subset from a data frame. The data frame(x) looks like the followings(10 species with 3 measured traits): Species trait1trait2 trait3 sp1 sp1 ... sp2 sp2 ... sp10 sp10 ... It would be easy if we want trait values for most abundant species, we can do that with the following codes sp-table(x$Species) x[x$Species==names(sp)[1],] but why it doesn't work if we want to select traits values for more than one species(most abundant two species) with similar codes x[x$Species==names(sp)[1:2],] And there must be other solutions for this problem. Looking forward for your help. Thanks in advance! __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
[R] subset of data frame
Hi, everyone I met a small problem when I want take a subset from a data frame. The data frame(x) looks like the followings(10 species with 3 measured traits): Species trait1trait2 trait3 sp1 sp1 ... sp2 sp2 ... sp10 sp10 ... It would be easy if we want trait values for most abundant species, we can do that with the following codes sp-table(x$Species) x[x$Species==names(sp)[1],] but why it doesn't work if we want to select traits values for more than one species(most abundant two species) with similar codes x[x$Species==names(sp)[1:2],] And there must be other solutions for this problem. Looking forward for your help. Thanks in advance! __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
[R] bargraph.CI
hello, I had a problem with the function bargraph.CI. bargraph.CI draws a figure according to the alphabet sequence of the factor used. For example, I have a factor with for levels CK, N5, N10, N15, but the bars appear in CK,N10,N15,N5 order(alphabet sequence), but I want the bars to appear CK, N5, N10, N15(treat level sequence). Do you have any ideas to realize the goal? Thank you! Yuanzhi __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
[R] volume of ellipsoid
Hi, everyone! I have a matrix X(n*p) which is n samples from a p-dimensional normal distribution. Now I want to make the ellipsoid containing (1-α)% of the probability in the distribution based on Mahalanobis distance: μ:(x-μ)'Σ^(-1)(x-μ)≤χ2p(α) where x and Σ is the mean and variance-covariance matrix of X. Are there some functions in R which can plot the ellipsoid and calculate the volume (area for p=2, hypervolume for p3) of the ellipsoid? I only find the ellipsoidhull function in cluster package, but it deal with ellipsoid hull containing X, which obvious not the one I want. After that, a more difficult is the following. If we have a series of matrix X1, X2, X3,… Xm which follow different p-dimensional normal distributions. And we make m ellipsoids (E1, E2, … Em) for each matrix like the before. How can we calculate the volume of union of the m ellipsoids? One possible solution for this problem is the inclusion-exclusion principle: V(⋃Ei)(1≤i≤m)= V(Ei)(1≤i≤m)-∑V(Ei⋂Ej)(1≤ij≤m)+∑V(Ei⋂Ej⋂Ek)(1≤ijk≤m)+(-1)^(m-1)V(E1⋂…⋂Em) But the problem is how to calculate the volume of intersection between 2, 3 or more ellipsoids. Are there some functions which can calculate the volume of intersection between two region or functions which directly calculate the volume of a union of two region(the region here is ellipsoid). OR yo you have any good ideas solving this problem in R? Thank you all in advance! Yuanzhi __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.