[R] writing data into files whose names are in a vector

Jeff Newmiller jdnewmil at dcn.davis.CA.us
Sat Jul 14 17:31:37 CEST 2012


I/O is not greatly improved by vectorization, except that whole files being read or written as units is faster than looping over rows. 
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Sent from my phone. Please excuse my brevity.

Raghuraman Ramachandran <optionsraghu at gmail.com> wrote:

>Thx Jeff. I could use a loop no doubt but I thought that will reduce
>the
>speed and I was thinking there could be a vectorisation idea. I will
>try
>your way. Cheers.
>
>On Sat, Jul 14, 2012 at 3:51 PM, Jeff Newmiller
><jdnewmil at dcn.davis.ca.us>wrote:
>
>> You have to wrap the write calls in some kind of loop. For your
>example,
>> you could use a for loop. If you have multiple rows of one name you
>might
>> look into the dlply function from the plyr package and use lapply to
>do the
>> actual write calls.
>>
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>> Jeff Newmiller                        The     .....       .....  Go
>Live...
>> DCN:<jdnewmil at dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live
>> Go...
>>                                       Live:   OO#.. Dead: OO#.. 
>Playing
>> Research Engineer (Solar/Batteries            O.O#.       #.O#.  with
>> /Software/Embedded Controllers)               .OO#.       .OO#. 
>rocks...1k
>>
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>> Sent from my phone. Please excuse my brevity.
>>
>> Raghuraman Ramachandran <optionsraghu at gmail.com> wrote:
>>
>> >GuRus
>> >
>> >How do I use the write function (or write.table or write.csv) to
>> >achieve
>> >the following please?
>> >
>> >age=c(32,37,39)
>> >names=c("john","peter","jake")
>> >
>> >I would like create in a directory 3 files each named as
>> >john.csv,peter.csv
>> >and jake.csv and each file have data from the age vector. That is
>> >jon.csv
>> >will contain 32, peter.csv will contain 37 and jake.csv will contain
>> >39.
>> >
>> >Thanks for the help.
>> >
>> >Raghu
>> >
>> >       [[alternative HTML version deleted]]
>> >
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>> >and provide commented, minimal, self-contained, reproducible code.
>>
>>



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