Sum with condition
Hi,
On Wed, Nov 2, 2011 at 8:44 AM, Celine <bellard.celine at gmail.com> wrote:
CELLCD AreaProtected ? 8928 ? ? ?52.39389 ? 8928 ? ? ?41.91511 ? 8929 ? ? ?21.21975 ? 8929 ? ? ?63.65925 ? 8930 ? ? ?26.08547 ? 8930 ? ? ?14.04602
You'll need to figure out how you want it to be combined with the original data frame, since there can't be empty cells, but:
dput(testdata)
structure(list(CELLCD = c(8928L, 8928L, 8929L, 8929L, 8930L,
8930L), AreaProtected = c(52.39389, 41.91511, 21.21975, 63.65925,
26.08547, 14.04602)), .Names = c("CELLCD", "AreaProtected"), class =
"data.frame", row.names = c(NA,
-6L))
aggregate(testdata$AreaProtected, by=list(CELLCD=testdata$CELLCD), FUN="sum")
CELLCD x 1 8928 94.30900 2 8929 84.87900 3 8930 40.13149
Sarah Goslee http://www.functionaldiversity.org