[R] [R-sig-hpc] Quickest way to make a large "empty" file on disk?

Jeff Ryan jeff.a.ryan at gmail.com
Thu May 3 00:42:37 CEST 2012


Look at the man page for dd (assuming you are on *nix)

A quick google will get you a command to try. I'm not at my desk or I would as well. 

Jeff

Jeffrey Ryan    |    Founder    |    jeffrey.ryan at lemnica.com

www.lemnica.com

On May 2, 2012, at 5:23 PM, Jonathan Greenberg <jgrn at illinois.edu> wrote:

> R-helpers:
> 
> What would be the absolute fastest way to make a large "empty" file (e.g.
> filled with all zeroes) on disk, given a byte size and a given number
> number of empty values.  I know I can use writeBin, but the "object" in
> this case may be far too large to store in main memory.  I'm asking because
> I'm going to use this file in conjunction with mmap to do parallel writes
> to this file.  Say, I want to create a blank file of 10,000 floating point
> numbers.
> 
> Thanks!
> 
> --j
> 
> -- 
> Jonathan A. Greenberg, PhD
> Assistant Professor
> Department of Geography and Geographic Information Science
> University of Illinois at Urbana-Champaign
> 607 South Mathews Avenue, MC 150
> Urbana, IL 61801
> Phone: 415-763-5476
> AIM: jgrn307, MSN: jgrn307 at hotmail.com, Gchat: jgrn307, Skype: jgrn3007
> http://www.geog.illinois.edu/people/JonathanGreenberg.html
> 
>    [[alternative HTML version deleted]]
> 
> _______________________________________________
> R-sig-hpc mailing list
> R-sig-hpc at r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-hpc



More information about the R-help mailing list