[R] how to combine data of several csv-files

[Antje]

Hello,

sorry for this confusion but I don't know a better way to explain...
I have no problems to read in the files and to process them. I end up 
with a list of results like this:

 > ret
$A02.csv
[1] NA

$B02.csv
[1] 89.130435  8.695652  2.173913  0.000000  0.000000  0.000000  9.892473

$C02.csv
[1] 86.842105 10.526316  2.631579  0.000000  0.000000  0.000000 10.026385

$D02.csv
[1] 85.000000 10.000000  5.000000  0.000000  0.000000  0.000000  4.474273

$E02.csv
[1] 70.786517 13.483146  7.865169  5.617978  2.247191  0.000000 12.125341

$F02.csv
[1] 70.83333 14.16667 10.00000  2.50000  2.50000  0.00000 17.26619

$G02.csv
[1] 64.772727 13.636364  7.954545 11.363636  2.272727  0.000000 12.735166

$H02.csv
[1] NA

$A03.csv
[1] NA

and I have a matrix with categories like this:


 > classmatrix
   1  2
A NA NA
B NA "cat1"
C NA "cat1"
D NA "cat1"
E NA "cat2"
F NA "cat2"
G NA "cat2"
H NA NA


Now, I'm looking for a way to calculate the mean element wise for all 
results coming from the same category:

in this case the mean of the elements:

$B02.csv
$C02.csv
$D02.csv

(belonging to "cat1")

I just don't know, how to combine the result list with the categories...

Does it become clearer? Probably, I try to provide a simple example but 
this will take some time to prepare...

Thanks anyway!

Antje




8rino-Luca Pantani schrieb:
> I'm unclear to what it is your problem.
> Import files into data frame?
> Combine them in one dataframe?
> Some (written) examples of the files would help people to help you out.
> 
> An example on how to get help better and faster
>  >>>>>>>>>>>>
> I have several csv files in the following form
> V1 V2
> 1   4
> 0.3   56
> ................
> V1   V2
> 2.5   25
> 4.5  45
> .....................
> 
> I would like to import them in only one dataframe, and then recode a 
> column in order to get
> V1 V2 V3
> 1   4   file1
> 0.3   56   file1
> 2.5   25   file2
> 4.5  45   file2
> .....................
>  >>>>>>>>>>>>
> Antje ha scritto:
>> Hello,
>>
>> I'm looking for a solution for the following problem:
>>
>> 1) I have a folder with several csv files; each contains a set of 
>> measurement values
>>   
>