[R] densities from a list with data.frames

[Antje]

Of course, I know, but I cannot apply the function "density" to a data frame 
(which is the element of the list) but to a vector coming from a data frame. 
That's my problem I'd like to solve...



Richard.Cotton at hsl.gov.uk schrieb:
>> I have a list which consists of data frames (all data frames have the 
> same 
>> amount and type of columns but different length).
>> Now, I'd like to calculate for each data frame in the list the 
>> density function 
>> of the values of the fist column ($V1).
>>
>> This list could be an example:
>>
>> l <- list( data.frame(rnorm(100)), data.frame(rnorm(20)), data.
>> frame(rnorm(200)) )
> 
> If you want to do the same thing to every element of a list, lapply (or 
> sapply) is your friend.
> Try:
> 
> lapply(l, function(x) density(x[,1]))
> 
> Regards,
> Richie.
> 
> Mathematical Sciences Unit
> HSL
> 
> 
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