Direct sphere.py
From Werner KRAUTH
(Difference between revisions)
Revision as of 21:40, 22 September 2015 Werner (Talk | contribs) ← Previous diff |
Current revision Werner (Talk | contribs) |
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- | This page presents the program markov_disks_box.py, a Markov-chain algorithm for four disks in a square box of sides 1. | + | This page presents the program direct_sphere.py, a direct-sampling algorithm for uniform random points inside the three-dimensional unit sphere. |
__FORCETOC__ | __FORCETOC__ | ||
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=Program= | =Program= | ||
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- | import random | ||
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- | L = [[0.25, 0.25], [0.75, 0.25], [0.25, 0.75], [0.75, 0.75]] | ||
- | sigma = 0.15 | ||
- | sigma_sq = sigma ** 2 | ||
- | delta = 0.1 | ||
- | n_steps = 1000 | ||
- | for steps in range(n_steps): | ||
- | a = random.choice(L) | ||
- | b = [a[0] + random.uniform(-delta, delta), a[1] + random.uniform(-delta, delta)] | ||
- | min_dist = min((b[0] - c[0]) ** 2 + (b[1] - c[1]) ** 2 for c in L if c != a) | ||
- | box_cond = min(b[0], b[1]) < sigma or max(b[0], b[1]) > 1.0 - sigma | ||
- | if not (box_cond or min_dist < 4.0 * sigma ** 2): | ||
- | a[:] = b | ||
- | print L | ||
- | |||
- | =Version= | ||
- | See history for version information. | ||
- | |||
- | [[Category:Python]] | ||
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- | |||
- | |||
import random, math | import random, math | ||
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/ math.sqrt(x ** 2 + y ** 2 + z ** 2) | / math.sqrt(x ** 2 + y ** 2 + z ** 2) | ||
print x * length, y * length, z * length | print x * length, y * length, z * length | ||
+ | |||
+ | =Version= | ||
+ | See history for version information. | ||
+ | |||
+ | [[Category:Python]] | ||
+ | [[Category:Honnef_2015]] | ||
+ | [[Category:MOOC_SMAC]] |
Current revision
This page presents the program direct_sphere.py, a direct-sampling algorithm for uniform random points inside the three-dimensional unit sphere.
Contents |
[edit]
Description
[edit]
Program
import random, math nsamples = 100 for sample in xrange(nsamples): x, y, z = (random.gauss(0.0, 1.0), random.gauss(0.0, 1.0), random.gauss(0.0, 1.0)) length = random.uniform(0.0, 1.0) ** (1.0 / 3.0) \ / math.sqrt(x ** 2 + y ** 2 + z ** 2) print x * length, y * length, z * length
[edit]
Version
See history for version information.