similar to: find the permutation function of a sorting

Displaying 20 results from an estimated 10000 matches similar to: "find the permutation function of a sorting"

2018 May 23
3
find the permutation function of a sorting
Thanks, David. I got the answer from the web. Is there any easy way to permute a set (e.g., a set of characters) by the permutation it returns? Thanks, > x <- c(10,7,4,3,8,2) > sort(x, index.return=TRUE) $x [1] 2 3 4 7 8 10 $ix [1] 6 4 3 2 5 1 2018-05-23 10:49 GMT+08:00 David Winsemius <dwinsemius at comcast.net>: > > > > On May 22, 2018, at 10:06 PM, John
2018 May 23
0
find the permutation function of a sorting
> On May 22, 2018, at 10:57 PM, John <miaojpm at gmail.com> wrote: > > Thanks, David. > I got the answer from the web. > Is there any easy way to permute a set (e.g., a set of characters) by the permutation it returns? Thanks, > > > > x <- c(10,7,4,3,8,2) > > sort(x, index.return=TRUE) > $x > [1] 2 3 4 7 8 10 > > $ix > [1] 6 4 3 2
2018 May 23
3
find the permutation function of a sorting
> sort(c("bc","ac","dd"), index.return=TRUE) $x [1] "ac" "bc" "dd" $ix [1] 2 1 3 We have the permutation, namely 1-->2, 2-->1, 3-->3. How can I apply the permutation function to a new set c("D","E", "F")? so that the result is c("E","D", "F"). 2018-05-23 11:06
2018 May 23
0
find the permutation function of a sorting
Hello, Like David said, what you are trying to do with sort() can be done with order() in a much easier way. First, your code x <- sort(c("bc","ac","dd"), index.return=TRUE) Now, with function order() i <- order(c("bc", "ac", "dd")) y <- c("D","E", "F")[i] y #[1] "E" "D"
2018 May 23
0
find the permutation function of a sorting
> On May 22, 2018, at 10:06 PM, John <miaojpm at gmail.com> wrote: > > Hi, > > Is there any way to find the permutation function of the sorting and to > apply the function (or its inverse) elsewhere? > > For example, the following permutation function from the sorting in the > matrix form is > c(1,2,3), c(2,1,3) > >>
2010 Jan 28
2
Constrained vector permutation
Hello, I'm trying to permute a vector of positive integers > 0 with the constraint that each element must be <= twice the element before it (i.e. for some vector x, x[i] <= 2*x[i-1]), assuming the "0th" element is 1. Hence the first element of the vector must always be 1 or 2 (by assuming the "0th" element is 1). Similarly, the 2nd must always be below/= 4, the
2007 Oct 02
1
permutations of a binary matrix with fixed margins
J?r?me, As a first attempt, how about the function below. It works (or not) by randomly sorting the rows and columns, then searching the table for "squares" with the corners = matrix(c(1,0,0,1),ncol=2) and subtracting them from 1 to give matrix(c(0,1,1,0),ncol=2) (and vice versa). Randomized matrices can be produced as a chain where each permutation is seeded with the previous one.
2006 May 03
1
Permutation test of marked point pattern
Dear R users, I am trying to perform a hypothesis test on a marked point pattern. I would like to calculate the mean of the absolute value of the difference of marks between nearest neigbours, randomize the marks among points, then calculate this mean again. Ideally, I would test whether random mean values smaller than the observed mean value occur less than 5% of the time. I suppose 1000
2009 Nov 15
1
how to permute, simulate Markov chain
Hi all, I am new to R. Can someone please give me some hints in how to do the following things: 1- Get ONE permutation of a set. I have looked at the gregmisc package's permutations() method, but I just want to get one permutation at a time. 2- Simulate a Markov chain in R. For instance, I want to simulate the simple random walk problem, in which a person can walk randomly around 4 places.
2009 May 20
1
Comparing spatial distributions - permutation test implementation
Hello everyone, I am looking at the joint spatial distribution of 2 kinds of organisms (estimated on a grid of points) and want to test for significant association or dissociation. My first question is: do you know a nice technique to do that, considering that I have a limited number of points (36) but that they are repeated (4 times)? I did GLMs to test for correlations between the
2008 Nov 14
1
Generating unique permutations of a vector
Hi all, I try to generate sets of strategies that contain probability distributions for a defined number of elements, e.g. imagine an animal that can produce 5 different types of offspring and I want to figure out which percentage of each type it should produce in order to maximize its fitness. In order to do so, I need to calculate the fitness for all potential strategies. As an example, if I
2017 Dec 08
2
Curiously short cycles in iterated permutations with the same seed
I have noticed that when I iterate permutations of short vectors with the same seed, the cycle lengths are much shorter than I would expect by chance. For example: X <- 1:10 Xorig <- X start <- 112358 N <- 10 for (i in 1:N) { seed <- start + i for (j in 1:1000) { # Maximum cycle length to consider set.seed(seed) # Re-seed RNG to same initial state X <- sample(X)
2012 Apr 28
3
Writing a Permutation Function
Hi everyone, I am somewhat new to R and I am trying to write a permutation function such that it inputs a character vector and from an arbitrary length "n" which is the length of the combinations for the character vector. I know there are R packages for permutation but this is for an assignment. So far this is what I have: alphabet =
2012 Jun 09
2
Help with permutation function from Turner et al. 2010 (Ecology)
Hello, I'm using R code that includes a residual permutation that was written as a supplement to the paper: Turner et al. 2010. A general hypothesis-testing framework for stable isotopes ratios in ecological studies. Ecology 91:2227-2233. The supplemental code is available at: http://www.esapubs.org/archive/ecol/E091/157/suppl-1.htm When I execute the function, no warnings are given
2017 Dec 08
0
Curiously short cycles in iterated permutations with the same seed
Hi Boris, Do a search on "the order of elements of the symmetric group". (This search will also turn up homework questions and solutions.) You will understand why you are seeing this once you understand how a permutation is decomposed into cycles and how the order relates to a partition of n (n=10 in your case). Enjoy! Eric On Fri, Dec 8, 2017 at 6:39 AM, Boris Steipe <boris.steipe
2010 Jan 19
1
restricted permutations in permtest()?
Hallo List, I'm trying to implemement a restricted permutation scheme in permutest(). More precisely I have dependence in my data that should be allowed for in the permutation - I simulated the problem in the example of the vegan documentation p.24: library(vegan) data(varespec) ## Bray-Curtis distances between samples dis <- vegdist(varespec) ## First 16 sites grazed, remaining 8 sites
2006 Jul 20
3
Permutation Distribution
Hallo Is there an elegant way to do the following: Dataset consists of 2 variables: var1: some measurements, and var2: a grouping variable with two values, 1 and 2. There are (say) 10 measurements from group 1 and 15 measurements from group 2. The idea is to study the permutation distribution of mean(group 1) * mean(group2). One way would be to permute 1s and 2s and select the corresponding
2009 Nov 12
2
A combinatorial optimization problem: finding the best permutation of a complex vector
Hi, I have a complex-valued vector X in C^n. Given another complex-valued vector Y in C^n, I want to find a permutation of Y, say, Y*, that minimizes ||X - Y*||, the distance between X and Y*. Note that this problem can be trivially solved for "Real" vectors, since real numbers possess the ordering property. Complex numbers, however, do not possess this property. Hence the
2005 Nov 29
2
permutation test for linear models with continuous covariates
Hi I was wondering if there is a permutation test available in R for linear models with continuous dependent covariates. I want to do a test like the one shown here. bmi<-rnorm(100,25) x<-c(rep(0,75),rep(1,25)) y<-rnorm(100)+bmi^(1/2)+rnorm(100,2)*x+bmi*x H0<-lm(y~1+x+bmi) H1<-lm(y~1+x+bmi+x*bmi) anova(H0,H1) summary(lm(y~1+x+bmi)) But I want to use permutation testing to
2011 Jan 24
2
Masking commands - Permutation in gregmisc and e1071
I am using the function permutations from the package *gregmisc*. However, I am also making use of the package *e1071*, which also contains a function called permutations. I want to use the function permutations from the * gregmisc* package, however, the other package is masking this function. This happens both when I load the *e1071* package before *gregmisc* and when I load *e1071* after I load