[R] how does a valid subscript can produce an "subscript out of bounds" error?

[Patrick Burns]

I think you are somewhere between
Circle 8.2.6 of 'The R Inferno'

http://www.burns-stat.com/documents/books/the-r-inferno/

and the basics of subscripting

http://www.burns-stat.com/documents/tutorials/impatient-r/more-r-subscript/

Pat

On 05/07/2014 15:19, Witold E Wolski wrote:
> Thank you. You example helped to FIX IT.
>
> The problem is I guess somehow related to:
>> class(msexp$pepinfo$transition_group_id)
> [1] "factor"
>
> and the whole R type conversion , riddle.
>
> For subscripts my intuition is:  either require integer or do the
> "cast" to the rowname type (character).
> However, it seems that R somehow prefers to cast factors to integers...
>
> it seems that %in% "casts" both vectors to the same type. But to which one?
>
> Oh, I guess all this is neatly explained in the R standard ... but
> websearching for it just returns:
> standard deviation
>
>
> a frustrated R user.
>
> On 5 July 2014 02:18, Duncan Murdoch <murdoch.duncan at gmail.com> wrote:
>> On 04/07/2014, 6:35 PM, Witold E Wolski wrote:
>>> how does a valid subscript (see first 2 lines) can produce an
>>> "subscript out of bounds" error (see line 4)?
>>>
>>>
>>> 1> sum(!rownames(msexp$rt) %in% msexp$pepinfo$transition_group_id)
>>> [1] 0
>>> 2> sum(!msexp$pepinfo$transition_group_id %in% rownames(msexp$rt))
>>> [1] 0
>>> 3> class(msexp$rt)
>>> [1] "matrix"
>>> 4> msexp$rt = as.matrix(msexp$rt[msexp$pepinfo$transition_group_id,])
>>> Error in msexp$rt[msexp$pepinfo$transition_group_id, ] :
>>>    subscript out of bounds
>>>>
>>>
>>
>>> x <- matrix(1,1,1)
>>> rownames(x) <- colnames(x) <- "23"
>>> 23 %in% rownames(x)
>> [1] TRUE
>>> x[23,]
>> Error in x[23, ] : subscript out of bounds
>>
>
>
>

-- 
Patrick Burns
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twitter: @burnsstat @portfolioprobe
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