Hi.
I've been puzzling about how to replace the nested loops below. The idea
is that the B dataframe has rows with a posix datetime and the C
dataframes has posix Start and End times. I want to assign a value to
the observations in B based in intersecting the appropriate
time-interval in C. I haven't been able to discern a more efficient way
to do this. Any suggestions would be most appreciated.
brows = dim(B)[1]
mrows = dim(C)[1]
for (i in 1:brows ) {
for (j in 1:mrows ) {
if (B$Datetime[i] >= C$DT_Start[j] & B$Datetime<=C$DT_End[j]){
B$Site[i] = C$Proximity[j]
}
}
}
--
John Helly, University of California, San Diego / San Diego Supercomputer
Center / Scripps Institution of Oceanography / 760 840 8660 mobile / stonesteps
(Skype) / stonesteps7 (iChat) / http://www.sdsc.edu/~hellyj
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
