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total CPU time in Matlab - what is the equivalent in R?
4 messages · Gopi Goteti, Jeff Newmiller, William Dunlap +1 more
Google is your friend http://www.ats.ucla.edu/stat/r/faq/timing_code.htm http://r.research.att.com/benchmarks/ --------------------------------------------------------------------------- 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 --------------------------------------------------------------------------- Sent from my phone. Please excuse my brevity.
Gopi Goteti <gopi.goteti at gmail.com> wrote:
I am trying to compare the speed of my R code with that reported by the authors of a reference paper who used Matlab. The authors of the paper state "Total CPU time for the algorithm was 10 s for the ...on a modest mobile 2.2 GHz Pentium processor running MATLAB v.6". I am using proc.time (similar to the example shown in ?proc.time) to determine the speed of my R code. Could someone please tell me whether "user" time or "system" time is the equivalent of total CPU time reported by Matlab. Thanks GG [[alternative HTML version deleted]]
______________________________________________ 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.
I didn't notice a discussion of what system or user time meant in those two articles. (The first correctly says that system.time() is a more convenient way to time things, as it calls proc.time() before and after your expression and subtracts. It also does garbage collection before the timing, so you get more consistent results.) CPU time is essentially user time plus system time. User time is time spent in R itself. System time is time spent by the kernel of the operating system doing things that R asked it to do (e.g., finding a file, reading a file, perhaps getting the time). What is considered system time depends on your operating system. There is some time spent switching between user and kernel mode and I don't know who gets charged for that time. Elapsed time is usually what counts in the end. Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com
-----Original Message----- From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of Jeff Newmiller Sent: Sunday, August 26, 2012 11:13 PM To: Gopi Goteti; r-help at r-project.org Subject: Re: [R] total CPU time in Matlab - what is the equivalent in R? Google is your friend http://www.ats.ucla.edu/stat/r/faq/timing_code.htm http://r.research.att.com/benchmarks/ --------------------------------------------------------------------------- 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 --------------------------------------------------------------------------- Sent from my phone. Please excuse my brevity. Gopi Goteti <gopi.goteti at gmail.com> wrote:
I am trying to compare the speed of my R code with that reported by the authors of a reference paper who used Matlab. The authors of the paper state "Total CPU time for the algorithm was 10 s for the ...on a modest mobile 2.2 GHz Pentium processor running MATLAB v.6". I am using proc.time (similar to the example shown in ?proc.time) to determine the speed of my R code. Could someone please tell me whether "user" time or "system" time is the equivalent of total CPU time reported by Matlab. Thanks GG [[alternative HTML version deleted]]
______________________________________________ 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.
______________________________________________ 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.
Maybe the unix time command comes in handy (provided you work with linux)? http://en.wikipedia.org/wiki/Time_(Unix) Best Jan -----Urspr?ngliche Nachricht----- Von: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] Im Auftrag von William Dunlap Gesendet: Montag, 27. August 2012 16:38 An: Jeff Newmiller; Gopi Goteti; r-help at r-project.org Betreff: Re: [R] total CPU time in Matlab - what is the equivalent in R? I didn't notice a discussion of what system or user time meant in those two articles. (The first correctly says that system.time() is a more convenient way to time things, as it calls proc.time() before and after your expression and subtracts. It also does garbage collection before the timing, so you get more consistent results.) CPU time is essentially user time plus system time. User time is time spent in R itself. System time is time spent by the kernel of the operating system doing things that R asked it to do (e.g., finding a file, reading a file, perhaps getting the time). What is considered system time depends on your operating system. There is some time spent switching between user and kernel mode and I don't know who gets charged for that time. Elapsed time is usually what counts in the end. Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com
-----Original Message----- From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of Jeff Newmiller Sent: Sunday, August 26, 2012 11:13 PM To: Gopi Goteti; r-help at r-project.org Subject: Re: [R] total CPU time in Matlab - what is the equivalent in R? Google is your friend http://www.ats.ucla.edu/stat/r/faq/timing_code.htm http://r.research.att.com/benchmarks/ --------------------------------------------------------------------------- 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 ---------------------------------------------------------------------- ----- Sent from my phone. Please excuse my brevity. Gopi Goteti <gopi.goteti at gmail.com> wrote:
I am trying to compare the speed of my R code with that reported by the authors of a reference paper who used Matlab. The authors of the paper state "Total CPU time for the algorithm was 10 s for the ...on a modest mobile 2.2 GHz Pentium processor running MATLAB v.6". I am using proc.time (similar to the example shown in ?proc.time) to determine the speed of my R code. Could someone please tell me whether "user" time or "system" time is the equivalent of total CPU time reported by Matlab. Thanks GG [[alternative HTML version deleted]]
______________________________________________ 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.
______________________________________________ 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.
______________________________________________ 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.