[R] Evaluate output after each rep()

[Berton Gunter]

Of course I assume that everyone realizes that the simulation estimates (1 -
dbinom(100,200,p=.5))^6000. The loge of this quantity is -348, btw. So this
is trivially computable, but I assume that this is an exercise of some sort.

-- Bert Gunter
Genentech Non-Clinical Statistics
South San Francisco, CA
 

> -----Original Message-----
> From: r-help-bounces at stat.math.ethz.ch 
> [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of 
> Adaikalavan Ramasamy
> Sent: Monday, February 06, 2006 9:35 AM
> To: macmanes at berkeley.edu
> Cc: r-help at stat.math.ethz.ch
> Subject: Re: [R] Evaluate output after each rep()
> 
> I do not fully understand what you mean by "stop". If you 
> mean terminate
> the whole function, then something like
> 
>  sim <- function(nn, mustExist=100){
> 
>    for (ii in 1:nn){
>        ee <- rep(rbinom(6000, 200, .5), ii)
> 
>        if( any(ee!=mustExist) )
>            stop( paste("Iteration", ii, "did not contain", mustExist, 
>                        ". Terminating function \n") )
>    }
>  
>    ## Do something further ##
>  }
> 
> 
> But generally, I want to just resample again till I get the 
> desired length.
> 
>  sim <- function(nn, mustExist=100){
> 
>    counter <- 0;  ii <- 1
> 
>    while( counter <= nn ){
> 
>        ee <- rep(rbinom(6000, 200, .5), ii)
> 
>        if( any(ee!=mustExist) ){
>            warning(paste( "Iteration", ii, "did not contain", 
> mustExist, 
>                            ". Resampling again\n") )
>        } else {
>          counter <- counter + 1
>          ii      <- ii + 1
>          ## Do something further ##
>       }
>    }
>  }
> 
> You can turn off the branch that returns the warnings if it 
> gets annoying.
> 
> BTW, why do you want to use rep(.., ii) ?
> 
> Regards, Adai
> 
> 
> 
> 
> If you want to count how many times out
> 
> 
> 
> On Mon, 2006-02-06 at 09:03 -0800, Matthew MacManes wrote:
> > Hi R-Help,
> > 
> > I'm trying a develop a test simulation where i evaluate the 
> probability 
> > of not getting a value of 100 from the function 
> rbinom(6000, 200, .5) 
> > [indeed, a very small probability].  At the end of each 
> rep, I would 
> > like to evaluate the output, continue with the loop if the output 
> > contains the value 100, stop if the output lacks a 100.
> > 
> > How do I get R to evaluate the output after each rep?
> > 
> > 
> >  >sim <- function(nn){
> >  >   for (ii in 1:nn){
> >  >      ee=rep(rbinom(6000, 200, .5), ii)
> >  >         if (any(ee==100))
> >  >      }
> > 
> > Thanks,
> > Matt MacManes
> > ********************************************************
> > Matthew D. MacManes
> > PhD Student
> > UC- Berkeley
> > Department of Integrative Biology
> > Museum of Vertebrate Zoology
> > 3101 VLSB #3140
> > Berkeley, CA 94720
> > (510)642-7782
> > EMAIL: macmanes at berkeley.edu
> > WEBSITE: http://ib.berkeley.edu/labs/lacey/
> > 
> > ______________________________________________
> > R-help at stat.math.ethz.ch mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide! 
> http://www.R-project.org/posting-guide.html
> >
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide! 
> http://www.R-project.org/posting-guide.html
>