[R] lapply returns NULL ?

[Rui Barradas]

Hello,

Try the following.

res <- lapply(foo, function(x) if(x[1] == 1 )  x  )
res[!sapply(res, is.null)]

Hope this helps,

Rui Barradas

Em 12-07-2014 14:25, ce escreveu:
>
>
> Dear all,
>
> I have a list of arrays :
>
> foo<-list(A = c(1,3), B =c(1, 2), C = c(3, 1))
>
>> foo
> $A
> [1] 1 3
>
> $B
> [1] 1 2
>
> $C
> [1] 3 1
>
>> if( foo$C[1] == 1 ) foo$C[1]
>
>>   lapply(foo, function(x) if(x[1] == 1 )  x  )
>
> $A
> [1] 1 3
>
> $B
> [1] 1 2
>
> $C
> NULL
>
> I don't want to list $C NULL  in the output. How I can do that ?
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