Maybe:
cbind(df,rbind(NA,apply(log(df),2,diff)))
Bart
Vishal Belsare wrote:
I have a dataframe say:
date price_g price_s
0.34 0.56
0.36 0.76
. .
. .
. .
and so on. say, 1000 rows.
Is it possible to add two columns to this dataframe, by computing say
diff(log(price_g) and diff(log(price_s)) ?
The elements in the first row of these columns cannot be computed, but
can I coerce this to happen and assign a missing value there? It would
be really great if I could do that, because in this case I don't have
to re-index my transformed series to the dates again in a new
dataframe.
Thanks in anticipation.
Vishal Belsare
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide
http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.