similar to: A Math question

I am not a pure Statistics background and therefore please forgive me if this question (which is not R related either) is too trivial. In many Statistics literature I find following statement: "restrictions in different coefficients matrices have to be imposed to ensure uniqueness of the parametrization". Can somebody tell me what is the meaning of Uniqueness in the parametrization?

Hi all, in R I have?Sys.timezone() function to get the current working Time zone. However I want to have a vector to get the list of all available time zones, like say, LETTERS gives me all letters. Is there any function like that? Thanks in advance,

This is some interesting: > -8^(1/3) [1] -2 > x=(-8:8) > y=x^(1/3) > y [1] NaN NaN NaN NaN NaN NaN NaN NaN 0.000000 1.000000 [11] 1.259921 1.442250 1.587401 1.709976 1.817121 1.912931 2.000000 So, can anybody explain this?! (Why is x[1]^(1/3)=y[1]=NaN, but -8^(1/3)=-2?) Thx!!! [[alternative HTML version deleted]]

deaRs, I want to build a covariance matrix out of the data from a binary file, that I can read in chunk by chunk, with each chunk containing a single observation vector X. I wonder how to do that most efficiently, avoiding the calculation of the full symmetric matrices XX'. The trivial non-optimal approach boils down to something like: Q <- matrix(rnorm(100000),ncol=200) M <-

Hi, I am trying to plot several columns in different graphs in columns and rows. The first column of my data file is the time, and the third is the 'elevation angle' with 19 different numbers. I would like to plot the rest of the columns with the x axis as time and the individual angles in different colours. Here is the code I am using right now. It plots the different columns with time,

I am pretty new to R. So this may be an easy question for most of you. ? I would like to calculate the squared distances of a large set (let's say 20000) of vectors (let's say dimension of 5) to a fixed vector. ? Say I have a data frame MY_VECTORS with 20000 rows and 5 columns, and one 5x1 vector y. I would like to efficiently calculate the squared distances?between each of the 20000

Dear all, I have a large matrix with about 2500 variables, and 100 rows. I would like to calculate the means of the every 10 variables starting from 1:2500 and saving the results as a vector or matrix. How can I do that? Alternatively, How can I create 250 subset matrices in the order of variables 1:2500 in groups of 10 from the single matrix which had initially 2500 variables ? I guess I have

Hello! I'm trying to build a lower triangular matrix (with zeros in the diagonal) from a particular dataframe. The matrix I have to construct has 203 rows and 203 columns and that makes 20503 values to be included within (that's why I can't do it manually). To illustrate the dataframe I have, I'll give you an example of a dataframe and matrix with dimensions 6x6 (to make it

Dear all R users, I am wondering is there any procedure exists on R to fetch data directly from "http://www.ncdex.com/Market_Data/Spot_price.aspx" and save it in some time series object, without filling any field in that website. Can somebody point me whether it is possible? Thanks and regards, [[alternative HTML version deleted]]

I've been wondering what L means in the R computing context, and was wondering if someone could point me to a reference where I could read about it, or tell me what it's called so that I can search for it myself. (L by itself is a little too general for a search term). I encounter it in strange places, most recently in the "save" documentation. save(..., list = character(0L),

Hello to all again :) Again, I have an issue with my homework. I was troubling myself for two days, and I still can't get it :( So, if someone can help me, I would be so grateful... HOMEWORK 1. I need to draw function, random walk take the length of walk, and its in 2D. As a result, I have to take matrix in which are i-lines of matrix, written coordinates on i-steps radnom.walk <-

Hi, Virsh destroy is always failing with below error. [host:~]$ virsh destroy XYZ--2 error: Failed to destroy domain XYZ--2 error: Requested operation is not valid: domain is not running [host:~]$ virsh list --all Id Name State ---------------------------------------------------- - XYZ--2 shut off [host:~]$ host:~]$ libvirtd --version

Hi, I'm trying to set the minimum and maximum in a parallel plot, but trying xlim=c(-1,1) gives strange results. Am I missing something? The call I give is: parallel(~X[,c(6,9,12,15,18)]|X$ff,X,panel=panel.parallel.new,groups=X$protein,layout=c(3,1),xlim=c(-1,1)) Besides, I would like to add a reference line to the plot, but can't find how to do that. I hope someone can give me a

hi, anyone to know a tool that will display more friendly output ... probably a tree like structure (if no cross sections occur)... OR a top like output... thanx raptor _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/

On 15/04/2018 17:26, Marc Girondot via R-help wrote: > Le 15/04/2018 ? 17:56, alireza daneshvar a ?crit?: >> break-down point > > Can you explain more what you plan to do and give an example of what you > have tried to do until now to do a "break down point" in R. Perhaps a > "break down point" is common in your field, but I have no idea about > what

Hello R-helpers, I am trying to search for string that includes the caret symbol, using the following code: grepl("latitude^2",temp) And R doesn't like that. It gives me: > temp<-c("latitude^2","latitude and latitude^2","longitude^2","longitude and longitude^2") > temp [1] "latitude^2" "latitude and

Dear R-users, I would like to apply a function (more precisely sd()) over the third dimension of a three-dimension array. The function apply would be interesting but the chosen function can only be applied on the rows and columns of the array according to the help file. I can use a loop to cut the array in matrices and then use apply for each replication, but it's not very nice. A small

Hi everyone, I saw this problem dealt with here: http://markmail.org/search/list:r-project?q=integrate#query:list%3Ar-project%20integrate+page:1+mid:qczmyzr676pgmaaw+state:results but no one answered that request that I can tell. I'm having the same problem. I'm having problems passing arguments to functions that I'd like to integrate. I could swear this worked in the past, but I

Hi Alex, this should be related to the "las" argument of "par()" but actually it does not seem to be parametered in scatterplot3d. Searching the net for "scatterplot3d las" provides a link to: https://stackoverflow.com/questions/25458652/specifying-the-orientation-of-the-axes-labels-in-scatterplot3d You may try the solution that is provided in this link or consider

Hi, I would like to rotate the x axis tick labels by 45 degrees. Using the code below, could someone please provide an example? Many Thanks In Advance, Alex library("scatterplot3d") mydf=data.frame(rate=seq(158, 314) ,age=seq(1, 157) ,market_date=seq(as.Date("2000/1/1"), as.Date("2003/1/1"), by="7 days"))