R help - Dec 2012 - Analyze multiple data set simultaneoulsy

Hi, everyone:



I have multiple dataset (say 100) in different subdirectory. They have same
name and exactly same format. I want to get summary for some columns for
each of these dataset (such as mean, SD etc), and list the summary in one
output file. It is for sure not effective if I do this one by one. Can
anyone advise me how to do it ‘on the fly’ using R?



More specifically, I wish to accomplish 2 jobs:

1), Import those 100 dataset to R. I will then have 100 data frames.

2), Analyze these 100 data frames simultaneously.



I am a newbie for R. Any suggestion would be greatly appreciated.



Thank you very much.



Mindy

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Mindy-
>
> If the sub-directories are named in a structured way --- say sd1, sd2,
> sd3, ..., sd100 --- then one option is a simple for-loop.  Something like
> the code below.
>
> -tgs
>
> directory.path <- '~/blahblah/'  # or 'C:/blahblah/' for
windows
> sd.names <- paste(directory.path,'sd',1:100,sep="")
> output <- array(NA, dim=c(100, number.of.statistics) )
>
> for( i in 1:100){
> setwd(sd.names[i])
>
> ... Code to read file, and calculate stats ...
> ... Code to store stats in output array ...
>
> }
>
>
>
>
> On Thu, Dec 6, 2012 at 1:13 PM, Min Dong <mindydong@gmail.com> wrote:
>
>> Hi, everyone:
>>
>>
>>
>> I have multiple dataset (say 100) in different subdirectory. They have
>> same
>> name and exactly same format. I want to get summary for some columns
for
>> each of these dataset (such as mean, SD etc), and list the summary in
one
>> output file. It is for sure not effective if I do this one by one. Can
>> anyone advise me how to do it ‘on the fly’ using R?
>>
>>
>>
>> More specifically, I wish to accomplish 2 jobs:
>>
>> 1), Import those 100 dataset to R. I will then have 100 data frames.
>>
>> 2), Analyze these 100 data frames simultaneously.
>>
>>
>>
>> I am a newbie for R. Any suggestion would be greatly appreciated.
>>
>>
>>
>> Thank you very much.
>>
>>
>>
>> Mindy
>>
>>         [[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.
>>
>>
>
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