search for: iac0

...<many other numeric columns> AAA 0 .7 AAA 10 .6 AAA 0 .66 AAA 20 .45 (more AAA rows) (then AAB rows) 'Key' identifies the physical configuration ... rows with a given Key contain data for same window under various conditions. I want to add a column IAC0 containing, for each Key, the mean IAC of all rows with ProfA == 0. The general approach I think I need is approximately (the following is not known to run) -- 1) XS<-subset( X, ProfA < .01) to get the ProfA == 0 rows. This could be done implicitly as part of step 2, I suppose. 2) X0&l...