1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
|
# naive approximation: pi = 4 * (1 - /1/3 + 1/5 ...)
LIMIT = 50000
def time() ; nqp::time() ; end
def sprintf(fmt, *args) ; nqp::sprintf(fmt, args) ; end
pi_over_4 = 0.0
print 'hang on a few moments...'
start_time = time()
# sum terms in reverse order to reduce accumulated error
n = LIMIT;
while n > 0 do
m = 4.0*n - 1.0
pi_over_4 += 1/(m - 2) - 1/m
n -= 1
end
puts sprintf("(completed %d iterations in %.2f sec)",
LIMIT, (time() - start_time) / 1000000000.0)
pi = pi_over_4 * 4
puts pi
|
