Question

I am new in R and I am trying to do something really simple. I had load a txt file with four columns and now I want to get the minimum value of the second column.
This is the code that I have:

 ## Choose the directory of the file

 setwd("//Users//dkar//Desktop")

 ## Read the txt file

 data<-read.table("export_v2.txt",sep="",header=T)

 str(data)

 ##  this command gives me the minimum for all 4 columns!!
 a<-apply(data,2,min)

Actually, if I want to do something like this: min (data(:,2)). But I don’t know how to do it in R. Any help?

Answer 1

If you need minimal value for particular column

min(data[,2])

Note: R considers NA both the minimum and maximum value so if you have NA’s in your column, they return: NA. To remedy, use:

min(data[,2], na.rm=T)