Try this:
my.array <- replicate(10, data.frame(matrix(sample(9), 3)), simplify =
FALSE)
#2
lapply(my.array, replace, list = 3, values = newThirdColumn)
The solution was for matrices, the above works with data.frames.
On Thu, Sep 3, 2009 at 5:03 PM, Carlos Hernandez <carlos.u...@gmail.com>wrote:
>
> On Thu, Sep 3, 2009 at 4:34 PM, Henrique Dallazuanna <www...@gmail.com>wrote:
>
>> Try this:
>>
>> #1
>> lapply(my.array, '[', , 3)
>>
>>
> this works! thank you a lot!
>
>
>> #2
>> newThirdColumn <- sample(3)
>> lapply(my.array, replace, list = 7:9, values = newThirdColumn)
>>
>>
> i did not understand this last line, so far i couldn't make it work.
>
> would it be easier to replace the values (the third column of each matrix
> in my.array) using an array like in #1?
>
> thank you for your reply!
>
>
>> On Thu, Sep 3, 2009 at 11:16 AM, Carlos Hernandez
>> <carlos.u...@gmail.com>wrote:
>>
>>> Dear All,
>>> I created a list (of length Z) in the following way:
>>>
>>> my.array <- vector("list", Z)
>>>
>>> then i assigned a matrix (of T rows by N columns) in each of the elements
>>> of
>>> the list my.array in the following way:
>>>
>>> my.array[[i]] <- matrix.data ##( matrix.data has dimensions TxN, and i
>>> repeated this command for i from 1 to Z, the matrix.data contains only
>>> numeric data)
>>>
>>> and
>>> 1. i would like to extract all the third columns of each of the Z
>>> matrices
>>> stored in my.array (such that i get a new list only with the 3rd columns
>>> of
>>> each matrix in the elements of a new list)
>>>
>>> 2. i would like to know how could i replace all the 3rd columns of each
>>> matrix in my.array if i have a second matrix (size ZxT) with these
>>> columns.
>>>
>>> is there a simple way to do these tasks? i appreciate any hints or
>>> advice.
>>>
>>> Carlos
>>>
>>> [[alternative HTML version deleted]]
>>>
>>> ______________________________________________
>>> R-help@r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>> PLEASE do read the posting guide
>>> http://www.R-project.org/posting-guide.html
>>> and provide commented, minimal, self-contained, reproducible code.
>>>
>>
>>
>>
>> --
>> Henrique Dallazuanna
>> Curitiba-Paraná-Brasil
>> 25° 25' 40" S 49° 16' 22" O
>>
>
>
--
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40" S 49° 16' 22" O
[[alternative HTML version deleted]]
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