[R] Any way to apply TWO functions with tapply()?

[Fredrik Karlsson]

Hi,

What you can do is define your own function which takes a vector of
values, computes the statistics you want and then returns a string
which displays the output the way you want it. Then use this function
in your tapply call.

like (untested)

mySummary <- function(x) {

  paste(mean(x),sd(x),sep=",")

}

tapply(data$response, list(data$targets, data$conditions) ,mySummary)

Of course, if you need a different output format, then you'll have to
adapt the paste call.

/Fredrik

On Fri, May 7, 2010 at 11:39 AM, Phil Wieland <phwiel at gmx.de> wrote:
>
> I need to compute the mean and the standard deviation of a data set and would
> like to have the results in one table/data frame. I call tapply() two times
> and do then merge the resulting tables to have them all in one table. Is
> there any way to tell tapply() to use the functions mean and sd within one
> function call? Something like tapply(data$response, list(data$targets,
> data$conditions), c(mean, sd)).
>
> Thanks in advance.
> --
> View this message in context: http://r.789695.n4.nabble.com/Any-way-to-apply-TWO-functions-with-tapply-tp2133924p2133924.html
> Sent from the R help mailing list archive at Nabble.com.
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