#
# simple.S
#	
# demo program for gaussian mixture (2-dim)
#
# Splus code of the EM algorithm for mixture models
# 	copyright by Shotaro Akaho <s.akaho@aist.go.jp>
#                    AIST Neuroscience Research Instutute, Japan 
# Notice:
#  1. Only noncommercial use is allowed
#  2. Attach this header in the case of redistribution
#  3. If you find any bugs, it is strongly recommended to inform them to me.

# device init (if you want to use another device, modify the following) 
motif() 

# initialize a model (2 gaussian)
g <- list()
for(i in 1:2) {
  g[[i]] <- gauss(rnorm(2), diag(rnorm(2)^2)) 
  # initialization parameter shold be modified appropriately
}
g <- mixture(g)

# sample generator (Num_of_samples x 2 matrix)
# this part could be replaced by your data
x <- matrix(rnorm(100, c(0, 1)), ncol=2)
x <- rbind(matrix(rnorm(100, c(1, 0)), ncol=2))

# run the EM algorithm with printing the mean log likelihood
for(iter in 1:10) {
  g <- estimate(g, x)
  print(like.em(g, x))
}

# plot the result
plot.em(g, x)