38 lines
1.2 KiB
Python
38 lines
1.2 KiB
Python
import numpy as np
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import matplotlib.pyplot as plt
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from plotstyle import *
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def random_walk(n, rng):
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p = 0.25
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steps = rng.rand(n)
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xsteps = np.zeros(len(steps))
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ysteps = np.zeros(len(steps))
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xsteps[(steps>=0*p)&(steps<1*p)] = +1
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xsteps[(steps>=1*p)&(steps<2*p)] = -1
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ysteps[(steps>=2*p)&(steps<3*p)] = +1
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ysteps[(steps>=3*p)&(steps<4*p)] = -1
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x = np.hstack(((0.0,), np.cumsum(xsteps)))
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y = np.hstack(((0.0,), np.cumsum(ysteps)))
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return x, y
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if __name__ == "__main__":
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fig, ax = plt.subplots(figsize=cm_size(figure_width, 0.65*figure_width))
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fig.subplots_adjust(**adjust_fs(fig, right=1.0))
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rng = np.random.RandomState(42281)
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nmax = 500
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lcs = [colors['blue'], colors['red'], colors['orange'],
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colors['yellow'], colors['green']]
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for k in range(len(lcs)):
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x, y = random_walk(nmax, rng)
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ls = dict(**lsAm)
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ls['color'] = lcs[k%len(lcs)]
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ax.plot(x, y, **ls)
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ax.set_xlabel('Position $x_n$')
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ax.set_ylabel('Position $y_n$')
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ax.set_xlim(-30, 30)
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ax.set_ylim(-20, 20)
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ax.set_xticks(np.arange(-30, 31, 10))
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ax.set_yticks(np.arange(-20, 21, 10))
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fig.savefig("randomwalktwo.pdf")
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plt.close()
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