Try this:

formatC(c(1, 10, 100), width = 4, flag = '0')

On Fri, Sep 10, 2010 at 5:05 PM, Nick Matzke <matzke@berkeley.edu> wrote:

> Hi,
>
> Is there an easy way to convert numbers into a form such that they all have
> the same number of digits?
>
> e.g.:
> "1", "10", and "100"
>
> ...become...
>
> "0001", "0010", "0100" etc.
>
> I ask because I am producing a large number of files that need to sort
> consistently by filename.  Currently I get this kind of sorting:
>
> filename1
> filename10
> filename11
> filename12
> filename13
> filename14
> filename15
> filename16
> filename17
> filename18
> filename19
> filename2
> filename20
> filename21
> ...etc..
>
> which is annoying.  Ideally I'd have:
>
> filename0001
> filename0002
> filename0003
> filename0004
> filename0005
> filename0006
> filename0007
> filename0008
> filename0009
> filename0010
> filename0011
> ...etc..
>
> Basically I want to produce strings like "0010" without an elaborate hack.
>
> Thanks!
> Nick
>
>
>
>
> --
> ====================================================
> Nicholas J. Matzke
> Ph.D. Candidate, Graduate Student Researcher
> Huelsenbeck Lab
> Center for Theoretical Evolutionary Genomics
> 4151 VLSB (Valley Life Sciences Building)
> Department of Integrative Biology
> University of California, Berkeley
>
> Graduate Student Instructor, IB200A
> Principles of Phylogenetics: Systematics
> http://ib.berkeley.edu/courses/ib200a/index.shtml
>
> Lab websites:
> http://ib.berkeley.edu/people/lab_detail.php?lab=54
> http://fisher.berkeley.edu/cteg/hlab.html
> Dept. personal page:
> http://ib.berkeley.edu/people/students/person_detail.php?person=370
> Lab personal page: http://fisher.berkeley.edu/cteg/members/matzke.html
> Lab phone: 510-643-6299
> Dept. fax: 510-643-6264
> Cell phone: 510-301-0179
> Email: matzke@berkeley.edu
>
> Mailing address:
> Department of Integrative Biology
> 3060 VLSB #3140
> Berkeley, CA 94720-3140
>
> -----------------------------------------------------
> "[W]hen people thought the earth was flat, they were wrong. When people
> thought the earth was spherical, they were wrong. But if you think that
> thinking the earth is spherical is just as wrong as thinking the earth is
> flat, then your view is wronger than both of them put together."
>
> Isaac Asimov (1989). "The Relativity of Wrong." The Skeptical Inquirer,
> 14(1), 35-44. Fall 1989.
> http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htm
>
> ______________________________________________
> 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

	[[alternative HTML version deleted]]

