I am trying to simulate the probability that more than two students have the same birthday in a room full on n people. Currently I think my code is working properly, although I have to initially just run the first line of code to select my n value, then run the rest of the code separately (see below)
n = as.integer(readline(prompt = "Enter the number of students in a room:"))
sims = 10000
x = numeric(sims)
for (i in 1:sims){
s = sample(1:365, n, replace=TRUE)
x[i] = n - length(unique(s))}
samebday = length(which(x>0))/length(x)
samebday
How would I tidy this up so that the variable n is contained within the function? As soon as I try to convert this to a function as follows:
bday.prob = function(n){...}
then errors start occurring.
If you want to use the code you wrote before and simply wrap it into a function, you can do so by letting n and sims be user-defined input variables, like @42- mentioned.
Below is my solution, with minimal changes from what you provided:
bday.prob = function(n, sims){
#' @param n is the number of students in a room; user-defined
#' @param sims is the number of trials; user-defined
x = numeric(sims)
for (i in 1:sims){
s = sample(1:365, n, replace=TRUE)
x[i] = n - length(unique(s))
}
samebday = length(which(x > 0))/length(x)
return(samebday)
}
Use the function as follows:
bday.prob(n=<User choice>, sims=<User choice>)
or
bday.prob(n=as.numeric(readline(prompt = "Enter the number of students in a room:")), sims=100)
## Enter the number of students in a room: <User choice>