search for: deltact

Hi, I have a data-frame, r (column names below), that needs subsetting: date, time, strain, gene, deltact When I try to subset r by applying selection criteria on two columns I get an empty data frame. For example I would like to extract all rows that have time == 0h and strain == ROC. So, t <- subset(r, (r$time == "0h" && r$strain == "ROC"), select= c(time, strain, gene...

Hi, I have a data-frame r (shown below is a subset) with the following column names: date time sample vct norm hct deltact $time has 8 levels: 0h, 0.5h, .....24h. $deltact holds real numbers. I want to subset this dataframe by the levels of $time. For all the rows which have r$time == "0h" I would like to convert the present value of r$deltact to 0. Any pointers to a simple method to accomplish would be gre...