以柱状图的形式显示散点图的边缘分布。

import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid1 import make_axes_locatable

# Fixing random state for reproducibility
np.random.seed(20200614)

# the random data
x = np.random.randn(1000)
y = np.random.randn(1000)


fig, ax = plt.subplots(figsize=(5.5, 5.5))

# the scatter plot:
ax.scatter(x, y)

# Set aspect of the main axes.
ax.set_aspect(1.)

# create new axes on the right and on the top of the current axes
divider = make_axes_locatable(ax)
# below height and pad are in inches
ax_histx = divider.append_axes("top", 1.2, pad=0.1, sharex=ax)
ax_histy = divider.append_axes("right", 1.2, pad=0.1, sharey=ax)

# make some labels invisible
ax_histx.xaxis.set_tick_params(labelbottom=False)
ax_histy.yaxis.set_tick_params(labelleft=False)

# now determine nice limits by hand:
binwidth = 0.25
xymax = max(np.max(np.abs(x)), np.max(np.abs(y)))
lim = (int(xymax/binwidth) + 1)*binwidth

bins = np.arange(-lim, lim + binwidth, binwidth)
ax_histx.hist(x, bins=bins)
ax_histy.hist(y, bins=bins, orientation='horizontal')

# the xaxis of ax_histx and yaxis of ax_histy are shared with ax,
# thus there is no need to manually adjust the xlim and ylim of these
# axis.

ax_histx.set_yticks([0, 50, 100])
ax_histy.set_xticks([0, 50, 100])

plt.show()

import matplotlib.pyplot as plt


def draw_text(ax):
    """
    Draw two text-boxes, anchored by different corners to the upper-left
    corner of the figure.
    """
    from matplotlib.offsetbox import AnchoredText
    at = AnchoredText("Figure 1a",
                      loc='upper left', prop=dict(size=8), frameon=True,
                      )
    at.patch.set_boxstyle("round,pad=0.,rounding_size=0.2")
    ax.add_artist(at)

    at2 = AnchoredText("Figure 1(b)",
                       loc='lower left', prop=dict(size=8), frameon=True,
                       bbox_to_anchor=(0., 1.),
                       bbox_transform=ax.transAxes
                       )
    at2.patch.set_boxstyle("round,pad=0.,rounding_size=0.2")
    ax.add_artist(at2)


def draw_circle(ax):
    """
    Draw a circle in axis coordinates
    """
    from mpl_toolkits.axes_grid1.anchored_artists import AnchoredDrawingArea
    from matplotlib.patches import Circle
    ada = AnchoredDrawingArea(20, 20, 0, 0,
                              loc='upper right', pad=0., frameon=False)
    p = Circle((10, 10), 10)
    ada.da.add_artist(p)
    ax.add_artist(ada)


def draw_ellipse(ax):
    """
    Draw an ellipse of width=0.1, height=0.15 in data coordinates
    """
    from mpl_toolkits.axes_grid1.anchored_artists import AnchoredEllipse
    ae = AnchoredEllipse(ax.transData, width=0.1, height=0.15, angle=0.,
                         loc='lower left', pad=0.5, borderpad=0.4,
                         frameon=True)

    ax.add_artist(ae)


def draw_sizebar(ax):
    """
    Draw a horizontal bar with length of 0.1 in data coordinates,
    with a fixed label underneath.
    """
    from mpl_toolkits.axes_grid1.anchored_artists import AnchoredSizeBar
    asb = AnchoredSizeBar(ax.transData,
                          0.1,
                          r"1$^{\prime}$",
                          loc='lower center',
                          pad=0.1, borderpad=0.5, sep=5,
                          frameon=False)
    ax.add_artist(asb)


ax = plt.gca()
ax.set_aspect(1.)

draw_text(ax)
draw_circle(ax)
draw_ellipse(ax)
draw_sizebar(ax)

plt.show()