[R] Extracting elements from a list

[Adaikalavan Ramasamy]

Try

  sapply( Lst, function(m) m[1,1] )

Also note that to subset a list, you just need Lst[ 1:10 ] and not
Lst[[ 1:10 ]] (note the double square brackets).

Regards, Adai


Forest Floor wrote:
> Hi,
> 
> I would love an easy way to extract elements from a list.  
> 
> For example, if I want the first element from each of 10 arrays stored 
> in a list,  
> 
> Lst[[1:10]][1,1]  seems like a logical approach, but gives this error:  
> "Error: recursive indexing failed at level 3"
> 
> The following workaround is functional but can get annoying/confusing.  
> 
> first.element=vector()
> for (i in 1:10){ first.element=c(first.element, Lst[[i]][1,1])  }
> 
> Is there a better way to do this?   Thanks for any help!
> 
> Jeff
> 
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