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authorGuido van Rossum <guido@python.org>1991-06-04 20:36:54 (GMT)
committerGuido van Rossum <guido@python.org>1991-06-04 20:36:54 (GMT)
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+#! /usr/local/python
+
+# Print digits of pi forever.
+#
+# The algorithm, using Python's 'long' integers ("bignums"), works
+# with continued fractions, and was conceived by Lambert Meertens.
+#
+# See also the ABC Programmer's Handbook, by Geurts, Meertens & Pemberton,
+# published by Prentice-Hall (UK) Ltd., 1990.
+
+import sys
+
+def main():
+ k, a, b, a1, b1 = 2l, 4l, 1l, 12l, 4l
+ while 1:
+ # Next approximation
+ p, q, k = k*k, 2l*k+1l, k+1l
+ a, b, a1, b1 = a1, b1, p*a+q*a1, p*b+q*b1
+ # Print common digits
+ d, d1 = a/b, a1/b1
+ #print a, b, a1, b1
+ while d = d1:
+ # Use write() to avoid spaces between the digits
+ sys.stdout.write(`int(d)`)
+ # Flush so the output is seen immediately
+ sys.stdout.flush()
+ a, a1 = 10l*(a%b), 10l*(a1%b1)
+ d, d1 = a/b, a1/b1
+
+main()