[R] How to perform arithmetic across rows

Hi All, I have a data frame (myframe) with variables (columns) A,B,C and 100 records (rows) for each. Column A is numeric. I would like to append a column to myframe that subtracts the value in row 24 of A from row 1 of A. In this procedure the first 23 rows of the new column will necessarily be

Re: [R] Add title to color spectrum legend in xyplot

Thanks Deepayan, That's an easy fix and provides a nice graph. Nick -- View this message in context: http://n4.nabble.com/Add-title-to-color-spectrum-legend-in-xyplot-tp1678456p1692375.html Sent from the R help mailing list archive at Nabble.com. __

[R] Add title to color spectrum legend in xyplot

Hi, I have a plot that is essentially the same as that in Figure 5.6 of "Lattice - Multivariate Data Visualization with R". The key difference is that I would like to add a title to top of the grey color spectrum legend, but have thus far been unsuccessful. I've tried a variety of options, but to

[R] How can I return rows from a data frame with maximum value by factor?

Hi, I'm new to R and new to this forum. I'm struggling with trying to extract certain rows of data from my data.frame. The data.frame has eleven columns. Among those columns are "FISH_ID" and "DATE_TIME". FISH_ID is a factor. For each of my 21 unique FISH_IDs (levels) I have a few to a few thousa

Re: [R] How can I return rows from a data frame with maximum value by factor?

Solved my own question by looking at some other threads. For those who may be intersted, here was the solution to my problem. do.call(rbind,lapply(split(data.frame,FISH_ID),function(x)x[which.max(x$DATE_TIME),])) -- View this message in context: http://n4.nabble.com/How-can-I-return-rows-from-a