注解

此笔记本可在此处下载： 1_Advanced_Plotting.ipynb

高级绘图

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
from matplotlib import cm
%matplotlib nbagg

def func(x, y):
    """
    A nice looking mapping.
    """
    r = (x**2 + y**2)**.5
    theta = np.where( r != 0., np.arccos(x/r) * np.sign(y), 0.)
    z =  (1. / (r + 5.)**.5) * np.sin(2. * np.pi * r / 3.) * np.cos(4 * theta)
    return z

x = np.linspace(-3., 3., 101)
y = np.linspace(-3., 3., 101)
X, Y = np.meshgrid(x, y)
X

array([[-3.  , -2.94, -2.88, ...,  2.88,  2.94,  3.  ],
       [-3.  , -2.94, -2.88, ...,  2.88,  2.94,  3.  ],
       [-3.  , -2.94, -2.88, ...,  2.88,  2.94,  3.  ],
       ...,
       [-3.  , -2.94, -2.88, ...,  2.88,  2.94,  3.  ],
       [-3.  , -2.94, -2.88, ...,  2.88,  2.94,  3.  ],
       [-3.  , -2.94, -2.88, ...,  2.88,  2.94,  3.  ]])

Y

array([[-3.  , -3.  , -3.  , ..., -3.  , -3.  , -3.  ],
       [-2.94, -2.94, -2.94, ..., -2.94, -2.94, -2.94],
       [-2.88, -2.88, -2.88, ..., -2.88, -2.88, -2.88],
       ...,
       [ 2.88,  2.88,  2.88, ...,  2.88,  2.88,  2.88],
       [ 2.94,  2.94,  2.94, ...,  2.94,  2.94,  2.94],
       [ 3.  ,  3.  ,  3.  , ...,  3.  ,  3.  ,  3.  ]])

Z = func(X, Y)

/home/lcharleux/Documents/Informatique/anaconda/envs/myconda1/lib/python3.6/site-packages/ipykernel_launcher.py:6: RuntimeWarning: invalid value encountered in true_divide

fig = plt.figure()
ax = fig.add_subplot(1, 1, 1)
ax.set_aspect("equal")
cont = plt.contourf(X, Y, Z, 10, cmap = cm.jet)
cbar = plt.colorbar(cont)
cbar.set_label("Amplitude, $z$")
plt.xlabel("Position, $x$")
plt.ylabel("Position, $y$")
plt.contour(X, Y, Z, 10, colors = "black")
plt.show()

<IPython.core.display.Javascript object>