-
Notifications
You must be signed in to change notification settings - Fork 3
/
brownian.py
37 lines (30 loc) · 981 Bytes
/
brownian.py
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
26
27
28
29
30
31
32
33
34
35
36
37
#-----------------------------------------------------------------------
# brownian.py
# python brownian.py 1
# python brownian.py .5
# python brownian.py .05
#-----------------------------------------------------------------------
import sys
import math
import stddraw
import stdrandom
#-----------------------------------------------------------------------
def curve(x0, y0, x1, y1, var, s):
if (x1 - x0) < .01:
stddraw.line(x0, y0, x1, y1)
return
xm = (x0 + x1) / 2.0
ym = (y0 + y1) / 2.0
delta = stdrandom.gaussian(0, math.sqrt(var))
curve(x0, y0, xm, ym+delta, var/s, s)
curve(xm, ym+delta, x1, y1, var/s, s)
#-----------------------------------------------------------------------
def main(argv):
H = float(argv[1])
stddraw.createWindow()
s = 2 ** (2*H) # or this: s = math.pow(2, 2*H)
curve(0, .5, 1.0, .5, .01, s)
stddraw.show()
stddraw.wait()
if __name__ == '__main__':
main(sys.argv)