#=====================================================
# Simulation of the probability distribution of success
# count.
#=====================================================

#-----------------------------------------------------
# 1.  Function to generate sequence of successes and
# failures.  Arguments:  number of trials is n, success
# probability on any given trial is p.  Function returns
# vector x of 0's and 1's.
#-----------------------------------------------------
outcomes=function(n,p) {
  u=runif(n)
  x=1*(u<=p)
  return(x)
}

#-----------------------------------------------------
# 2.  Simulate n trials num.sets times.
# Store counts of successes in hits.
#-----------------------------------------------------

n=30
p=.26
num.sets=10000
hits=numeric(num.sets)
for (i in 1:num.sets) {
  hits[i]=sum(outcomes(n,p))
}

#-----------------------------------------------------
# 3.  Plot histogram of hits.
#-----------------------------------------------------
bounds=(0:31)-.5
hist(hits,breaks=bounds,freq=FALSE)