circuitpython/tests/perf_bench/bm_pidigits.py

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# Source: https://github.com/python/pyperformance
# License: MIT
# Calculating some of the digits of π.
# This benchmark stresses big integer arithmetic.
# Adapted from code on: http://benchmarksgame.alioth.debian.org/
def compose(a, b):
aq, ar, as_, at = a
bq, br, bs, bt = b
return (aq * bq,
aq * br + ar * bt,
as_ * bq + at * bs,
as_ * br + at * bt)
def extract(z, j):
q, r, s, t = z
return (q * j + r) // (s * j + t)
def gen_pi_digits(n):
z = (1, 0, 0, 1)
k = 1
digs = []
for _ in range(n):
y = extract(z, 3)
while y != extract(z, 4):
z = compose(z, (k, 4 * k + 2, 0, 2 * k + 1))
k += 1
y = extract(z, 3)
z = compose((10, -10 * y, 0, 1), z)
digs.append(y)
return digs
###########################################################################
# Benchmark interface
bm_params = {
(50, 25): (1, 35),
(100, 100): (1, 65),
(1000, 1000): (2, 250),
(5000, 1000): (3, 350),
}
def bm_setup(params):
state = None
def run():
nonlocal state
nloop, ndig = params
ndig = params[1]
for _ in range(nloop):
state = None # free previous result
state = gen_pi_digits(ndig)
def result():
return params[0] * params[1], ''.join(str(d) for d in state)
return run, result