Replacing all occurrences of a value in a data frame column

Question

How can I replace, for example, all "-sh2", in a column (V2) with -100, as in the following dataframe:

V1  V2  V3
p1  -sh2    13
p2  23  29
p3  17  25
p4  -sh2    34

Thanks

Start by reading this [**basic introductory text on vectors and assignment**](http://cran.r-project.org/doc/manuals/R-intro.html#Index-vectors) — Simon O'Hanlon, Jan 09 '14 at 14:39

score 4 · Accepted Answer · answered Jan 09 '14 at 14:42

4

dat$V2 <- replace(as.character(dat$V2), dat$V2 == "-sh2", "-100")

answered Jan 09 '14 at 14:42

Sven Hohenstein

score 2 · Answer 2 · answered Jan 09 '14 at 15:35

2

There are many ways to do this. You can use the replace solution above. Or use ifelse. Or even:

my.df$V2[my.df$V2 == "-sh2"] <- -100

answered Jan 09 '14 at 15:35

rrs

1

Many thanks Simon, Sven and rrs for the perfect solutions. – user27976 Jan 09 '14 at 15:49

2 Answers2