[R] do.call without arguments?

[Peter Dalgaard]

Antje wrote:
> Hello,
>
> I have a vector containing strings of simple operation methods.
>
> methods <- c("mean","sd","median")    e.g.
>
> Now, I'd like to apply these methods to my data and I thought, I could make a 
> do.call. But these methods don't need any further arguments... Do I have to 
> create an empty argument list?
>
> I wanted to use a tapply( data, factor, ??? do.call ??? )
>
> Can anybody help how to solve this problem?
>
>   
Not sure what you mean by "any further arguments", but I wouldn't use
do.call here:

> names(methods)<-methods
> with(airquality,
+  lapply(methods, function(f) tapply(Ozone,Month,FUN=f, na.rm=T)))
$mean
       5        6        7        8        9
23.61538 29.44444 59.11538 59.96154 31.44828

$sd
       5        6        7        8        9
22.22445 18.20790 31.63584 39.68121 24.14182

$median
 5  6  7  8  9
18 23 60 52 23



-- 
   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
  c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
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