R help - Apr 2007 - Extracing "Interval of Time" in seconds in R

Dear List,

I want to let R calculate the time (run-time) it
requires to run a self-written simulation function. I
tried as follows: it 

enables me to see the starting and finishing time
points. 

#############################
"sim.result" <- function(nsim, ...){

Starting <- date()

... # calculations #

final.result <- ... # Output for display #
cat("# of Iterations used =", nsim, "\n" )

Ending <- date()

cat("Start of Program at", Starting, "\n" )
cat("End of Program at", Ending, "\n" )

return(print(final.result, quote = FALSE))
}
#############################

But how about I want the results in difference of
statring and ending time in seconds only (say, in
output, I need the 

function to say that "the program took 597 secornds to
run the whole simulation"), not in all these
format(Sys.time(), "%a 

%b %d %H:%M:%S %Y")

Again, I tried in the following way, but it does not
seem to do the trick
> starting<-Sys.time()
> ending<-Sys.time()
> format(diff(ending,starting), "%H:%M:%S")
Error in Ops.POSIXt(lag, differences) : * not defined
for "POSIXt" objects
> as.numeric(format(ending, "%H:%M:%S")) 
[1] NA


How should I proceed?



Thanks for your valuable time.
Thanks in advance.


Mohammad Ehsanul Karim
Using Windows Xp, R 2.3.1
Institute of Statistical Research and Training, 
University of Dhaka

?system.time

might be what you're looking for.

Ted.

Mohammad Ehsanul Karim wrote on 04/23/2007 03:53 PM:
> Dear List,
>
> I want to let R calculate the time (run-time) it
> requires to run a self-written simulation function. I
> tried as follows: it 
>
> enables me to see the starting and finishing time
> points. 
>
> #############################
> "sim.result" <- function(nsim, ...){
>
> Starting <- date()
>
> ... # calculations #
>
> final.result <- ... # Output for display #
> cat("# of Iterations used =", nsim, "\n" )
>
> Ending <- date()
>
> cat("Start of Program at", Starting, "\n" )
> cat("End of Program at", Ending, "\n" )
>
> return(print(final.result, quote = FALSE))
> }
> #############################
>
> But how about I want the results in difference of
> statring and ending time in seconds only (say, in
> output, I need the 
>
> function to say that "the program took 597 secornds to
> run the whole simulation"), not in all these
> format(Sys.time(), "%a 
>
> %b %d %H:%M:%S %Y")
>
> Again, I tried in the following way, but it does not
> seem to do the trick
>
>   
>> starting<-Sys.time()
>> ending<-Sys.time()
>> format(diff(ending,starting), "%H:%M:%S")
>>     
> Error in Ops.POSIXt(lag, differences) : * not defined
> for "POSIXt" objects
>   
>> as.numeric(format(ending, "%H:%M:%S")) 
>>     
> [1] NA
>
>
> How should I proceed?
>
>
>
> Thanks for your valuable time.
> Thanks in advance.
>
>
> Mohammad Ehsanul Karim
> Using Windows Xp, R 2.3.1
> Institute of Statistical Research and Training, 
> University of Dhaka
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
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> PLEASE do read the posting guide
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>   

-- 
 Dr E.A. Catchpole  
 Visiting Fellow
 Univ of New South Wales at ADFA, Canberra, Australia
    _	  and University of Kent, Canterbury, England
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