question on aggregate
On Mon, Jan 10, 2011 at 8:23 PM, analyst41 at hotmail.com
<analyst41 at hotmail.com> wrote:
an example available on the net goes like
df
?identifier quantity 1 ? ? ? ? ?1 ? ? ? 10 2 ? ? ? ? ?1 ? ? ? 20 3 ? ? ? ? ?2 ? ? ? 30 4 ? ? ? ? ?1 ? ? ? 15 5 ? ? ? ? ?2 ? ? ? 10 6 ? ? ? ? ?3 ? ? ? 20
aggregate(df$quantity, by=list(df$identifier), sum)
?Group.1 ?x 1 ? ? ? 1 45 2 ? ? ? 2 40 3 ? ? ? 3 20 I'd like Group.1 to retain the name "identifier" and would like to control what "x" get called in the output. ?Thanks.
Try these:
aggregate(quantity ~ identifier, df, sum)
identifier quantity 1 1 45 2 2 40 3 3 20
aggregate(df["quantity"], df["identifier"], sum)
identifier quantity 1 1 45 2 2 40 3 3 20
aggregate(list(Quantity = df$quantity), df["identifier"], sum)
identifier Quantity 1 1 45 2 2 40 3 3 20
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