[R] Function gives numeric(0) for every input

[R. Michael Weylandt <michael.weylandt@gmail.com>]

Also, vectorize this puppy - that's how you really get the best performance out of R, but in this case it will easily get rid of your problem. 

Michael

On Nov 19, 2011, at 11:31 PM, Peter Langfelder <peter.langfelder at gmail.com> wrote:

> Well, you assign numeric(0) or numeric(0)+1, which is still
> numeric(0). No wonder the return value is always numeric(0).
> 
> You probably need to replace numeric(0) simply by 0. Numeric(0) does
> not mean 0, it means a numeric vector of length zero (i.e., empty).
> 
> HTH,
> 
> Peter
> 
> On Sat, Nov 19, 2011 at 6:52 PM, alex_janssen <janssena at uoguelph.ca> wrote:
>> Hi,
>> 
>> I am trying to code buffons needle in R for a class
>> 
>> This is my code w/ output from R, if anyone could tell me why this is
>> happening it would be amazing,
>> 
>> I can generate correct results without putting the steps into a function but
>> alas that is the assignment.
>>> buffon = function(n){
>> + x = NULL
>> + theta = NULL
>> + a = NULL
>> + phat = numeric(0)
>> + i = 1
>> +
>> + while ( i <= n){
>> + x[i] <- runif(1,0,1/2)
>> + theta[i] <- runif(1,0,pi/2)
>> + a[i] <- 1/2 * (sin(theta[i])) - x[i]
>> +
>> +
>> + if (a[i] <= 0)phat <- phat + 1
>> + else phat<-phat
>> + i <- i + 1
>> +
>> +  }
>> + return(phat)
>> + }
>>> buffon(10)
>> numeric(0)
>>> 
>> Thanks Again
>> 
>> the response should be the number of times a[i] is less than or equal to
>> zero, which i am calling phat
>> 
>> --
>> View this message in context: http://r.789695.n4.nabble.com/Function-gives-numeric-0-for-every-input-tp4087834p4087834.html
>> Sent from the R help mailing list archive at Nabble.com.
>> 
>> ______________________________________________
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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
> and provide commented, minimal, self-contained, reproducible code.