How to find highest value in a data frame?

Question

I have a dataframe x with this values:

   x1  x2  x3
1  NA   4   1
2  NA   3  NA
3   4  NA   2
4  NA   1  11
5  NA   2  NA
6   5  NA   1
7   5   9           


        

Answer 1

Use max() with the na.rm argument set to TRUE:

dat <- read.table(text="
   x1  x2  x3
1  NA   4   1
2  NA   3  NA
3   4  NA   2
4  NA   1  11
5  NA   2  NA
6   5  NA   1
7   5   9  NA
8  NA   2  NA", header=TRUE)

Get the maximum:

max(dat, na.rm=TRUE)
[1] 11