Hello!
I have a data frame like this one:
mydf<-data.frame(city=c("a","a","a","a","a","a","a","a","b","b","b","b","b","b","b","b"),
brand=c("x","x","y","y","z","z","z","z","x","x","x","y","y","y","z","z"),
value=c(1,2,11,12,111,112,113,114,3,4,5,13,14,15,115,116))
(mydf)
What I need to get is a data frame like the one below - cities as
rows, brands as columns, and the sums of the "value" within each
city/brand combination in the body of the data frame:
city x y z
a 3 23 336
b 7 42 231
I have written a code that involves multiple loops and subindexing -
but it's taking too long.
I am sure there must be a more efficient way of doing it.
Thanks a lot for your hints!
--
Dimitri Liakhovitski
Ninah Consulting
www.ninah.com
______________________________________________
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.
