matplotlib中创建axes的几种方法

大概有这么几种吧

.Figure.add_subplot
.Figure.add_axes
.pyplot.subplot
.pyplot.axes
.Figure.subplots
.pyplot.subplots

1 .Figure.add_subplot

https://matplotlib.org/stable/api/figure_api.html?highlight=figure%20add_subplot#matplotlib.figure.Figure.add_subplot

fig = plt.figure()

fig.add_subplot(231)
ax1 = fig.add_subplot(2, 3, 1)  # equivalent but more general

fig.add_subplot(232, frameon=False)  # subplot with no frame
fig.add_subplot(233, projection='polar')  # polar subplot
fig.add_subplot(234, sharex=ax1)  # subplot sharing x-axis with ax1
fig.add_subplot(235, facecolor="red")  # red subplot

ax1.remove()  # delete ax1 from the figure
fig.add_subplot(ax1)  # add ax1 back to the figure

2 .Figure.add_axes

https://matplotlib.org/stable/api/figure_api.html?highlight=figure%20add_subplot#matplotlib.figure.Figure.add_axes

rect = l, b, w, h
fig = plt.figure()
fig.add_axes(rect)
fig.add_axes(rect, frameon=False, facecolor='g')
fig.add_axes(rect, polar=True)
ax = fig.add_axes(rect, projection='polar')
fig.delaxes(ax)
fig.add_axes(ax)

3 .pyplot.subplot

https://matplotlib.org/stable/api/_as_gen/matplotlib.pyplot.subplot.html#matplotlib.pyplot.subplot
注意，这里有一个问题，原文是这样的：

import matplotlib.pyplot as plt
# plot a line, implicitly creating a subplot(111)
plt.plot([1, 2, 3])
# now create a subplot which represents the top plot of a grid
# with 2 rows and 1 column. Since this subplot will overlap the
# first, the plot (and its axes) previously created, will be removed
plt.subplot(211)

后面建立的211ax会覆盖第一个ax，如果不想这样，使用Figure.add_subplot或者plt.axes.

plt.subplot(221)

# equivalent but more general
ax1 = plt.subplot(2, 2, 1)

# add a subplot with no frame
ax2 = plt.subplot(222, frameon=False)

# add a polar subplot
plt.subplot(223, projection='polar')

# add a red subplot that shares the x-axis with ax1
plt.subplot(224, sharex=ax1, facecolor='red')

# delete ax2 from the figure
plt.delaxes(ax2)

# add ax2 to the figure again
plt.subplot(ax2)

# make the first axes "current" again
plt.subplot(221)

4 .pyplot.axes

https://matplotlib.org/stable/api/_as_gen/matplotlib.pyplot.axes.html#matplotlib.pyplot.axes

# Creating a new full window axes
plt.axes()
# Creating a new axes with specified dimensions and some kwargs
plt.axes((left, bottom, width, height), facecolor='w')

5 .Figure.subplots

https://matplotlib.org/stable/api/figure_api.html#matplotlib.figure.Figure.subplots

# First create some toy data:
x = np.linspace(0, 2*np.pi, 400)
y = np.sin(x**2)

# Create a figure
plt.figure()

# Create a subplot
ax = fig.subplots()
ax.plot(x, y)
ax.set_title('Simple plot')

# Create two subplots and unpack the output array immediately
ax1, ax2 = fig.subplots(1, 2, sharey=True)
ax1.plot(x, y)
ax1.set_title('Sharing Y axis')
ax2.scatter(x, y)

# Create four polar Axes and access them through the returned array
axes = fig.subplots(2, 2, subplot_kw=dict(projection='polar'))
axes[0, 0].plot(x, y)
axes[1, 1].scatter(x, y)

# Share a X axis with each column of subplots
fig.subplots(2, 2, sharex='col')

# Share a Y axis with each row of subplots
fig.subplots(2, 2, sharey='row')

# Share both X and Y axes with all subplots
fig.subplots(2, 2, sharex='all', sharey='all')

# Note that this is the same as
fig.subplots(2, 2, sharex=True, sharey=True)

6 .pyplot.subplots

https://matplotlib.org/stable/api/_as_gen/matplotlib.pyplot.subplots.html#matplotlib.pyplot.subplots

# First create some toy data:
x = np.linspace(0, 2*np.pi, 400)
y = np.sin(x**2)

# Create just a figure and only one subplot
fig, ax = plt.subplots()
ax.plot(x, y)
ax.set_title('Simple plot')

# Create two subplots and unpack the output array immediately
f, (ax1, ax2) = plt.subplots(1, 2, sharey=True)
ax1.plot(x, y)
ax1.set_title('Sharing Y axis')
ax2.scatter(x, y)

# Create four polar axes and access them through the returned array
fig, axs = plt.subplots(2, 2, subplot_kw=dict(projection="polar"))
axs[0, 0].plot(x, y)
axs[1, 1].scatter(x, y)

# Share a X axis with each column of subplots
plt.subplots(2, 2, sharex='col')

# Share a Y axis with each row of subplots
plt.subplots(2, 2, sharey='row')

# Share both X and Y axes with all subplots
plt.subplots(2, 2, sharex='all', sharey='all')

# Note that this is the same as
plt.subplots(2, 2, sharex=True, sharey=True)

# Create figure number 10 with a single subplot
# and clears it if it already exists.
fig, ax = plt.subplots(num=10, clear=True)