[R] lapply and paste

Ed Siefker ebs15242 at gmail.com
Wed Mar 28 20:44:37 CEST 2012


Thank you, I was confused about that.  What exactly is lapply for then,
if R handles this kind of thing automatically?  Are there functions that are
not "vectorized"?


On Wed, Mar 28, 2012 at 1:37 PM, R. Michael Weylandt
<michael.weylandt at gmail.com> wrote:
> I think you're confused about the need for lapply -- paste is
> vectorized so this
>
> paste("filename_", suff, ".ext", sep = "")
>
> will work. But if you want to use lapply (for whatever reason) try this:
>
> lapply(suff, function(x) paste("filename_", x, ".ext", sep = "")
>
> Michael
>
> On Wed, Mar 28, 2012 at 2:31 PM, Ed Siefker <ebs15242 at gmail.com> wrote:
>> I have a list of suffixes I want to turn into file names with extensions.
>>
>> suff<- c("C1", "C2", "C3")
>> paste("filename_", suff[[1]], ".ext", sep="")
>> [1] "filename_C1.ext"
>>
>> How do I use lapply() on that call to paste()?
>> What's the right way to do this:
>>
>> filenames <-  lapply(suff, paste, ...)
>>
>> ?
>>
>> Can I have lapply() reorder the arguments to FUN?
>>
>> ______________________________________________
>> R-help at 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.



More information about the R-help mailing list