search for: somefactor

Hi All, I'm looking for ways to compute aggregate statistics (with the aggregate function) but with an option for sorting and selecting a subset of the data frame. For example, I have would like to turn this : aggregate(myDataframe$TargetValue,list(SomeFactor = myDataframe$SomeFactor),mean) into something like aggregate(myDataframe$TargetValue,list(SomeFactor = myDataframe$SomeFactor),mean, sort=DESCENDING, subset=0.33) where sort would sort TargetValue per factor level and subset would be (for example) a value between 0 and 1. The example above wou...

Dear list, just to put it in a simple way: i read.csv from csv file to create a gdata then, create array gdata34 however, when making a loop for assigning gdata34[1,m]<-gdata[m,4], this is what happen gdata[1,4] 's real value is 10354, however, the gdata34[1,4] turns to be 883 then i checked the type: gdata[1,4] is integer, while gdata34[1,4] is double. Can any one give me some help

I have a column in a data frame that has a class of "Date" and a mode of "numeric". When I: max(df$Date) My output stays in Date format, i.e. "2006-01-03". However, when I run the following statment: tapply(df$Date, df$SomeFactor, max) my output looks like this: 9129 9493 9861 10226 10591 10956 11320 11687 12052 12417 The returned object is of mode "numeric" and class "array". Each array element is of mode "numeric" and class "numeric". I believe that this is the in...

I want to plot quantitative data as a function of three two-level factors. How do I group the bars on a barplot by level through labeling and spacing? Here <http://www.thomaslevine.org/sample_multiple-factor_barplot.png>'s what I'm thinking of. Also, I'm pretty sure that I want a barplot, but there may be something better. Tom [[alternative HTML version deleted]]

...ng like: result <- by(mydata, mydata$some_factor, function (x) { # do something to create a vector v with length(v) == nrow(x) return(v) }) # now result has a big list, argh... how do I put it neatly back into the mydata data frame? for (i in unique(mydata$some_factor) { mydata$newvar[mydata$somefactor ==i] <- result[[i]] } What should I be doing instead of this? David Hugh-Jones Post-doctoral Researcher Max Planck Institute of Economics, Jena http://davidhughjones.googlepages.com [[alternative HTML version deleted]]

Hello all, I have generated a principal components regression model using the pcr() function from the PLS package (R version 2.12.0). I am getting a "non-conformable arguments" error when I try to use the predict() function on new data, but only when I try to read in the new data from a separate file. More specifically, when my data looks like this #########training data