how to perform log2 transform on specific columns in R [duplicate]

Question

I have a data frame like this:

d <-  
read.table(header=TRUE,text='
      gene       0h       4h      24h       48h      72h
1     MIB2 5.329502 5.202208 4.742011 4.8148886 2.263599
2 SLC35E2B 6.461612 6.599991 6.464688 6.5399660 6.378209
3   CALML6 5.200950 5.308204 5.848097 6.2346177 6.744116
4   CALML6 5.200950 5.308204 5.848097 6.2346177 6.744116
5  FAM213B 5.228090 5.379973 5.717725 5.7202588 6.204203
6   PRDM16 2.981332 1.538496 1.263351 0.6315327 3.622116')

and I would like to perform log2 transform on column 2:6 but keep the information of column one.

I am able to log transform column 2:6 with log(d[2:6],2) but then I lose the gene information.

Answer 1

If you want to save it back into the same data.frame, then simply use:

d[, 2:6] <- log(d[2:6], 2)
d

If you want to save it to a new object, first snag a copy:

d.new <- d
d.new[, 2:6] <- log(d[2:6], 2)
d.new

You can also use cbind if you'd like