[R] counting values with some conditions in a simulation

[Jeff Newmiller]

A) you need to reply-all to keep the discussion on the mailing list.

B) you need to post in plain text.

C) this has the arbitrary smell of homework. This is not a homework help line.

D) You are overwriting your accumulation variable "sumt" after each test. Since you are not handling this calculation in a vectorized manner, I suggest you use the "if ... else ... else" syntax to accomplish this. See the help for "if".
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Sent from my phone. Please excuse my brevity.

Sl K <s.karmv at gmail.com> wrote:

>Sorry, I forgot to include my code. Here is what I am trying to do.
>
>
>
>rep=10
>
>results<-numeric(rep)
>
>x<- data.frame(matrix(runif(10*15),15))
>
>y<- data.frame(matrix(runif(10*15),15))
>
>for (i in c(1:rep)){
>
>st<-data.frame(y=c(x[,i],y[,i]),samp=factor(c(rep("X",15),rep("Y",15))))
>
>stt<-st[order(st[,1]),]
>
>dt<-stt[1:30,]
>
>r<-as.vector( dt$samp)
>
> tt<-rle(r)$lengths[rle(r)$values == "X"]
>
>sumt<-sum(tt[1:3])
>
>sumt[sumt <=3] <- 0
>
> sumt[sumt>3]<- 1
>
>sums<-as.numeric(sumt)
>
>results[i] <- sums
>
>}
>
>xx<-as.vector(results)
>
>sum(xx)
>
>
>This was the original code I had, before I was just counting how many
>will
>give me a sum more than 3. Now, I want to show that if sumt<3 then 0,
>if
>sum>3 then 1, if sum=3, then generate a random number from uniform
>distribution, if this number is say less than 0.5 then it's 1, if
>greater
>than 0.5, then it's 0.
>
>Thank you very much for your help.
>
>
>On Fri, Nov 25, 2011 at 10:19 AM, Jeff Newmiller
><jdnewmil at dcn.davis.ca.us>wrote:
>
>> You need to read the posting guide. Provide a reproducible code
>sample,
>> simplified, with self-contained data.
>> You might find the "ave" function useful if you are working with
>> vectorized simulations.
>>
>---------------------------------------------------------------------------
>> 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.
>>
>> Sl K <s.karmv at gmail.com> wrote:
>>
>> >Dear R users,
>> >
>> >I am running simulations (1000), and in my simulation I am looking
>at
>> >specific sums. For example, if the sum is >=4 then count this, if
>say
>> ><3,
>> >then don't count, if the sum=3, then generate a random number from
>> >uniform
>> >distribution, if this number is say less than 0.5, then count this
>sum,
>> >if
>> >greater than 0.5, then don't count. I am having trouble with
>> >introducing
>> >this uniform number and decide whether to count 3 or not.  Any help
>or
>> >hint
>> >will be greatly appreciated. Thank you very much in advance
>> >
>> >       [[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.
>>
>>