I would describe myself as a competent Excel user but very much a beginner in R. There are lots of parallels between the two programs but lots of differences too. In this series I’m going to describe how to do some routine Excel tasks in R and any major differences between the two.
There are some great general resources available for people making the transition and I’ve listed some useful ones at the end.
So let’s start with min and max. Min and max themselves just return the minimum or maximum value of the arguments – numbers, vectors etc.
> max(c(105, 120, 230, 220) , 100)  230
To compare the values in two vectors in a pairwise fashion we need to use pmin and pmax.
> ref <- c(105, 120, 230, 220) > current <- c(100, 120,235,100) > pmin(ref,current)  100 120 230 100
This leads to something that is very easy to do in R but difficult in Excel because you need to overwrite existing data (I guess you would use a macro). I have a vector of reference stock prices called ref and a vector of current prices called current. I want to update the reference price to be the maximum of the reference price and the current price.
> ref <- c(105, 120, 230, 220) > current <- c(100, 120,235,100) > ref <- pmax(ref, current) > ref  105 120 235 220
Elements 1,2 and 4 stay the same but element 3 has been updated with the higher price.
General resources about R for Excel users: