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2 results for “from:George Nachman”

How to sum one column in a data frame keyed on other columns
George Nachman · Dec 12, 2006 · r-help

I have a data frame that looks like this: url time somethingirrelevant visits www.foo.com 1:00 xxx 100 www.foo.com 1:00 yyy 50 www.foo.com 2:00 xyz 25 www.bar.com 1:00 xxx...

How to sum one column in a data frame keyed on other columns
George Nachman · Dec 12, 2006 · r-help

Thanks, everyone, for the help! Bill: This looks like a really great general solution, but unfortunately I get an error when I call sumUp: Error in "[.data.frame"(dat, , key_list, drop = FALSE) : invalid subscript type I'm running 2...

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