[R] timing a function

[Peter Ehlers]

On 2010-05-17 10:49, Gustave Lefou wrote:
> Dear all,
>
> I have a function f(x).
>> ptm<- proc.time()
>> y=f(x)
>> proc.time() - ptm
>
> works fine for me.
>
> However it is not possible to write
>
>> system.time(y=f(x))
>
> and
>
>> system.time(f(x))
>
> does not store the value of f(x).
>
> Should I prefer the 3 lines with proc.time ?

No. You should be careful in your use of '=' which is only allowed at 
top level.

Try
  system.time(y <- f(x))

and see ?"=".

  -Peter Ehlers

>
> Thank you very much,
> Gustave
>
>
>
> 2010/5/4 Joris Meys<jorismeys at gmail.com>
>
>> ?system.time can help too.
>>
>> On Tue, May 4, 2010 at 11:07 PM, pdb<philb at philbrierley.com>  wrote:
>>
>>>
>>> Hi,
>>> I want to time how long a function takes to execute. Any clues on what to
>>> search for to achieve this?
>>>
>>> Thanks in advance.
>>> --
>>> View this message in context:
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>>> Sent from the R help mailing list archive at Nabble.com.
>>>
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>>
>>
>>
>> --
>> Joris Meys
>> Statistical Consultant
>>
>> Ghent University
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>>
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>>
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>> ______________________________________________
>> R-help at r-project.org mailing list
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>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html<http://www.r-project.org/posting-guide.html>
>> and provide commented, minimal, self-contained, reproducible code.
>>
>
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>
> ______________________________________________
> 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.
>