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Python matplotlib example 'wall-crossing'
Modules used in program:
import matplotlib.pyplot as plt
import numpy as np
python wall-crossing
Python matplotlib example: wall-crossing
# plt.contour assumes there are lines between theta = 0 and theta = 2*np.pi
import numpy as np
import matplotlib.pyplot as plt
#%matplotlib inline
plt.rcParams['figure.figsize']=7,7
# rm foo*.png
# convert foo*.png foo.gif
dt = 0.01
L = 5
t = np.arange(-L,L+dt, dt)
z = t[...,None]+1j*t[None,...]
N = 20
PP = np.polyval(P,z)
for k in np.arange(N):
print("%02d" %(k))
w = np.log(np.exp(2j*np.pi*(k*1.0/N))*PP)
ds = 0.05
plt.contour(t, t, w.imag%(2*np.pi), levels = 2*np.pi*np.arange(0,1, ds), colors=('#505050','#707070'), linewidth=1)
plt.contour(t, t, w.imag%(2*np.pi), levels = 2*np.pi*np.arange(0,1, 0.5), colors='w', linewidth=50)
plt.contour(t, t, w.real, levels = np.arange(0,5,0.1)**1, colors=('#A2D426','#6B6CED'))
L = 3
plt.xlim([-L,L])
plt.ylim([-L,L])
#plt.show()
plt.savefig('/home/jdm/Documents/math/foo-%02d.png'%(k))
plt.clf()
Python links
- Learn Python: https://pythonbasics.org/
- Python Tutorial: https://pythonprogramminglanguage.com