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+#	WICHMANN-HILL RANDOM NUMBER GENERATOR
+#
+#	Wichmann, B. A. & Hill, I. D. (1982)
+#	Algorithm AS 183: 
+#	An efficient and portable pseudo-random number generator
+#	Applied Statistics 31 (1982) 188-190
+#
+#	see also: 
+#		Correction to Algorithm AS 183
+#		Applied Statistics 33 (1984) 123  
+#
+#		McLeod, A. I. (1985)
+#		A remark on Algorithm AS 183 
+#		Applied Statistics 34 (1985),198-200
+#
+#
+#	USE:
+#	whrandom.random()	yields double precision random numbers 
+#				uniformly distributed between 0 and 1.
+#
+#	whrandom.seed()		must be called before whrandom.random()
+#				to seed the generator
+
+
+#	Translated by Guido van Rossum from C source provided by
+#	Adrian Baddeley.
+
+
+# The seed
+#
+_seed = [0, 0, 0]
+
+
+# Set the seed
+#
+def seed(x, y, z):
+	_seed[:] = [x, y, z]
+
+
+# Return the next random number in the range [0.0 .. 1.0)
+#
+def random():
+	from math import floor		# floor() function
+	#
+	[x, y, z] = _seed
+	x = 171 * (x % 177) - 2 * (x/177)
+	y = 172 * (y % 176) - 35 * (y/176)
+	z = 170 * (z % 178) - 63 * (z/178)
+	#
+	if x < 0: x = x + 30269
+	if y < 0: y = y + 30307
+	if z < 0: z = z + 30323
+	#
+	_seed[:] = [x, y, z]
+	#
+	term = float(x)/30269.0 + float(y)/30307.0 + float(z)/30323.0
+	rand = term - floor(term)
+	#
+	if rand >= 1.0: rand = 0.0	# floor() inaccuracy?
+	#
+	return rand
+
+
+# Initialize from the current time
+#
+def init():
+	import time
+	t = time.time()
+	seed(t%256, t/256%256, t/65536%256)
+
+
+# Make sure the generator is preset to a nonzero value
+#
+init()