similar to: means by column after split

We are building a package, and want to create S4 methods for both head and mean for our own BigMatrix class. Following the recommendation in "Writing R Extensions" we use exportMethods instead of export in NAMESPACE (this is described as being "clearer"). This works for head, but not for mean. Obviously we importFrom(utils, head), but don't need to do this for mean,

Hello , I can not get apply function to do what I want when doing stuff on rows. Let's say I want to divide the rows of matrix by their mean, the below show you get the same result weather you use 1 or 2, i.e. same result for columns than for means..:( Thanks a lot for the help, m = matrix( c(1,4,7,4,5,8,7,8,9), nrow = 3 ) divideByMean = function( v ){ return(

Full_Name: Chris Hane Version: 2.10.1 OS: Windows Submission from: (NULL) (198.203.181.181) When using barchart in the flexcust package, setting mcol=NULL to avoid the lollipops causes an error. Each panel shows the text message "Error using packet n replacement has length zero." where n is the panel number. > data(iris) > cl <- cclust(iris[,-5], k=3) > barplot(cl,

I am using the library(bigmemory) to handle large datasets, say 1 GB, and facing following problems. Any hints from anybody can be helpful. _Problem-1: _ I am using "read.big.matrix" function to create a filebacked big matrix of my data and get the following warning: > x = read.big.matrix("/home/utkarsh.s/data.csv",header=T,type="double",shared=T,backingfile

I read from external data source containing several columns. Each column represents value of a metric. The columns are time series data. I want to sort the resulting dataframe such that the column with the largest mean is the leftmost column, descending in colMean values to the right. I see many solutions for sorting rows based on some column characteristic, but haven't found any

I have been trying to produce a histogram that has two groups (male and female snakes) on the same graph (either superimposed or each frequency bar appears side by side). I found a couple of functions for superimposed histogram written by other people. The below is the codes I used for my data containing a column of svl (body size; snout-vent length) and another column of sex (male or female).

Hello: Is there a way to get a mean from values stored in different rows? The data looks like this: YEAR-1, JAN, FEB, ..., DEC YEAR-2, JAN, FEB, ..., DEC YEAR-3, JAN, FEB, ..., DEC What I want is the mean(s) for just the consecutive winter months: YEAR-1.DEC, YEAR-2.JAN, YEAR-2.FEB YEAR-2.DEC, YEAR-3.JAN, YEAR-3.FEB etc. Thanks.

I''m using the date_select and datetime_select helpers in my view, and they return Date classes from the params hash. But how do I work with Date classes, they don''t print human readable dates or times, Time classes work well I can use strftime("%H:%M") to print to the screen. Is it possible to convert a Date to a Time, Ive been tinkering in irb but have got

heya-- Been playing with dovecot today as I was learning about the features I haven't used yet like the director/proxy stuff. I setup a basic dovecot stack today which is 1 director and 1 IMAP dovecot server behind it. I have one user setup in MySQL and when I first changed from proxy mode to director mode I left the host column populated with the IMAP server. Once I confirmed this was