gen_random_friends.rb

#!/usr/bin/ruby
require 'securerandom'
require 'gsl'

module RandData
def create_random_friendship size
	friendships = ""
	while size != 0 do
		f1 = "RandFriend-" + SecureRandom.uuid;
		f2 = "RandFriend-" + SecureRandom.uuid;
		eval = "(EvaluationLink (stv 0.4 1.0) (PredicateNode \"friends\")
	        	(ListLink (ConceptNode \"#{f1}\")(ConceptNode \"#{f2}\")))"
		friendships = friendships + "\n" + eval
		size-=1
	end

	return friendships
end

def create_random_eval_links size, n = 10
#Lets create a SIZE number smokers and fried em to N individuals		
	scm_str = "" 
	rand_gen = GSL::Rng.alloc(1) #default generator is mt19973
	i = 0
	j = 0

	while i < size do
		smoker ='(ConceptNode "Smoker-' + SecureRandom.uuid+'")'
		smokes = sprintf "(EvaluationLink (stv %s 0.8)\n\t(PredicateNode 
		                   \"smokes\")\n\t\t(ListLink\n\t\t\t%s))", 0.2 , smoker
		has_cancer = sprintf "(EvaluationLink (stv %s 0.8)\n\t(PredicateNode
	                         	\"cancer\")\n\t\t(ListLink\n\t\t\t%s))", 0.1 , smoker
		scm_str = scm_str + smokes + "\n"  + has_cancer + "\n"

		while j < n do
			non_smoker = '(ConceptNode "NonSmoker-' + SecureRandom.uuid+'")'
		        friends = sprintf "(EvaluationLink (stv %s 0.8)\n\t(PredicateNode 
			                    \"friends\")\n\t\t(ListLink\n\t\t\t%s\n\t\t\t%s))", 
				            rand_gen.uniform.round(2).to_s, smoker, non_smoker
			scm_str = scm_str + "\n" + friends+ "\n"
			j = j + 1
		end
		i = i + 1
	end
	scm_str
end

end

def write_to_file(fname,str)
	File.open(fname, 'w') { |file| file.write(str) }
end

include  RandData

if __FILE__ == $0
	puts ARGV.to_s
	if ARGV.length < 2
		printf "usage %s <filename> <size> \n",$0
		exit      
	end

	printf "Writing %d random friendship relations to %s \n", ARGV[1].to_i, ARGV[0]
#	write_to_file(ARGV[0],RandData::create_random_friendship(ARGV[1].to_i))
	write_to_file(ARGV[0],RandData::create_random_eval_links(ARGV[1].to_i))
	printf "Done\n"
end