[R] Is this sapply behaviour normal?

[Wacek Kusnierczyk]

Kenn Konstabel wrote:
> On Thu, Jun 26, 2008 at 12:14 AM, Wacek Kusnierczyk <
> Waclaw.Marcin.Kusnierczyk at idi.ntnu.no> wrote:
>
>   
>>>     sapply(dats,function(x){sapply(x,min)})
>>>       
>> you can achieve the same with
>>
>> sapply(dats, sapply, min)
>>
>>
>>     
> Did you actually try it?
>
>   
>> dats <- data.frame(1:10,2:11)
>> sapply(dats,sapply,min)
>>     
>       X1.10 X2.11
>  [1,]     1     2
>  [2,]     2     3
>  [3,]     3     4
>  [4,]     4     5
>  [5,]     5     6
>  [6,]     6     7
>  [7,]     7     8
>  [8,]     8     9
>  [9,]     9    10
> [10,]    10    11
>
> Sapply doesn't (or can't?) pass arguments to another sapply -- maybe  the
> trick can be done without an anonymous function but not the way you
> suggested.
>
>   

did you actually read the original mail?  there dats was a *list* of
data frames.
try this:

d = data.frame(a=1:10. b=11:20)
l = list(a=d, b=d)
sapply(l, sapply, min)
sapply(l. function(d) sapply(d, min))

did you actually read the docs for sapply?  there ... stands for
optional arguments to FUN.
try this:

?sapply


vQ