search for: colsd

Hi people, If there is a fn "colMeans" why isn't there a "colSDs" etc Thanks, Phil. -- Philip Rhoades Pricom Pty Limited (ACN 003 252 275) GPO Box 3411 Sydney NSW 2001 Australia Mobile: +61:0411-185-652 Fax: +61:2:8923-5363 E-mail: pri at chu.com.au -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list...

...as unused argument (as expected). _Problem-2:_ I want to get a filebacked *sub*matrix of "x", say only selected columns: x[, 1:100]. Is there any way of doing that without actually loading the data into R memory. _ Problem-3 _There are functions available like: summary, colmean, colsd, ... for standard summary statistics. But is there any way to calculate other summaries say number of missing values or skewness of each variable, without loading the whole data into R memory. Regards Utkarsh

Hi, I am analysing gene expression data using the heatmap.2 function in R and I was wondering what is the formula of the "raw z-score" bar which shows the colors for each pixel. According to that post: https://mailman.stat.ethz.ch/pipermail/r-help/2006-September/113598.html, it is the (actual value - mean of the group) / standard deviation. But, mean of which group? Mean of the gene

Hi everyone, I have just started using R, and I have a simple question. How can I get the Standard deviation for rows. basically I am looking for something like "rowMeans()" but for Standard deviation (I tried "rowSds()" didn't exist) Thanks, -- View this message in context: http://www.nabble.com/Standard-deviation-for-rows-tp19998106p19998106.html Sent from the R

...weep(x, 1, rm)          retval$rowSDs <- sx <- apply(x, 1, sd, na.rm = na.rm)          x <- sweep(x, 1, sx, "/")      }      else if (scale == "column") {          retval$colMeans <- rm <- colMeans(x, na.rm = na.rm)          x <- sweep(x, 2, rm)          retval$colSDs <- sx <- apply(x, 2, sd, na.rm = na.rm)          x <- sweep(x, 2, sx, "/")      } So the z-score is calculated on either the row or column (or the default of "none"). I don't see how you can get something saying 'raw z-score'. I get either 'Row Z-Sc...