Re: [R] Recursive indexing failed at level 2

From: Jim Hargreaves <>
Date: Sat, 26 Jun 2010 13:29:18 +0100

On 06/26/2010 01:20 PM, Duncan Murdoch wrote:
> On 26/06/2010 7:53 AM, Jim Hargreaves wrote:
>> Dear fellow R users,
>> I am replacing elements of a list like so:
>> pulse_subset[[1:20]]=unlist(pulse[i])[1:20]
> If pulse is a list, then pulse[i] is also a list, with one element. I
> think you want pulse[[i]], which extracts element i.
Ahh, I specified pulse[i] has >20 values in my original mail. Basically pulse is a list 1000 elements long, with each element in pulse having between 1000 and 2000 elements of it's own. Pulse is a list of lists. Also as far as I am aware, [[ ]]'s should only be used when assigning values to elements of a list/vector.

unlist(pulse[1]) gives x1, x2, x3, x4, x5 etc. etc.
> If pulse_subset is a list, then pulse_subset[[1:20]] is equivalent to
> pulse_subset[[1]][[2]][[3]][[4]] ... [[20]], i.e. the syntax implies
> that it is a list containing a list etc, nested 20 levels deep. The
> error message is telling you that it's not. I'm not sure what your
> intention is in this case.
> Duncan Murdoch
>> where pulse is a list of lists, and pulse [i] has >20 values.
>> This gives the error "Recursive Indexing failed at level 2". But,
>> interestingly this instruction is part of a loop which has gone
>> through about 200,000 iterations before giving this error.
>> Actual code:
>> >
>> pulse_subset[[1:(length(unlist(pulse[i])[as.numeric(peak_start[i]):as.numeric(peak_end[i])]))]]
>> <- unlist(pulse[i])[as.numeric(peak_start[i]):as.numeric(peak_end[i])]
>> Error in
>> pulse_subset[[1:(length(unlist(pulse[i])[as.numeric(peak_start[i]):as.numeric(peak_end[i])]))]]
>> <- unlist(pulse[i])[as.numeric(peak_start[i]):as.numeric(peak_end[i])] :
>> recursive indexing failed at level 2
>> If anyone could shed some light I'd be rather grateful.
>> Regards,
>> Jim Hargreaves
>> ______________________________________________
>> mailing list
>> PLEASE do read the posting guide
>> and provide commented, minimal, self-contained, reproducible code.
> mailing list PLEASE do read the posting guide and provide commented, minimal, self-contained, reproducible code. Received on Sat 26 Jun 2010 - 12:32:19 GMT

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