Dear R family, I am a relative newbie and have been dabbling with R for a little while. Simple things really, but my employers are beginning to see the benefits of using R instead of excel. We have a remote monitoring station measuring groundwater levels. We download the date as a .csv file and up until now, we have been using excel to analyse the data. It’s been a hassle trying to wrestle with that damn program as my boss wants to do things that excel was never meant to do, so I’ve convinced my boss to give R a chance. It’s been a steep learning curve, but I’m fairly confident I can reduce the amount of labour involved in producing and improving the graphs we show our clients.
The groundwater levels are measured by pressure sensors lowered into the monitoring wells. After a certain time, the sensors were lowered further into the well, thus creating a disparity in the measurements. The data frame I import into R looks something like this: Date Waterhead (mm) Parameter 1 Paramater 2, etc. 10-01-01 100 10-01-02 105 10-01-03 101 10-01-04 99 10-01-05 85 10-01-06 200 # <- Sensor lowered# 10-01-07 199 10-01-08 195 10-01-09 185 10-01-10 170 For example, on the 10-10-06, the sensor was lowered by 115 mm. When I download the csv file, I download the data from the beginning of the measurement period. I then need to adjust the height by 115 mm to account for the lowering of the parameter. My question to you is how do I do that in R? I am after a formula or a manipulation that selects the first five measurements of a column in the data frame and adds a fixed amount. This is something that is added everytime I download the csv file and import it into R so that when I display my data, it is based on the following data frame: Date Waterhead (mm) 10-01-01 215 10-01-02 220 10-01-03 216 10-01-04 214 10-01-05 200 10-01-06 200 10-01-07 199 10-01-08 195 10-01-09 185 10-01-10 170 In short, I want to select a fixed number of rows from my data frame, add a constant to the rows of one of the columns, and insert the new values into their respective rows without affecting the subsequent rows. I hope I have produced a reproducible example, I have been searching high and low for a solution, but have come up against a brick wall. I feel I have read something that tackles this some time in the past, but can’t find it again. Thanks in advance! Sincerely, Michael Hopgood MRM Konsult AB -- View this message in context: http://r.789695.n4.nabble.com/Manipulation-tp3221260p3221260.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
