如何在极坐标图周围添加环绕轴？

Question

我在想办法把一个轴附加到我的极坐标投影上。新添加的轴应该像一个环一样围绕着原始极轴。在

为此，我尝试使用append_axes，这个除法器是通过polarmatplotlib投影ax创建的。在

但是，对于“outer”或任何类似于极轴投影的append_axes参数的选项都没有。 我得到了一个新的轴，而不是一个围绕着轴的环（见图）。在

是否有其他方法允许在现有极轴周围创建环形轴？

注意，我不想把它们放在同一把斧头上，因为刻度可能不同。在

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

plt.style.use("seaborn-white")
def synthesize(polar=False):
    fig = plt.figure()
    ax = fig.add_subplot(111, polar=polar)
    t = np.linspace(0,2*np.pi)
    r_sin = np.sin(t)
    r_cos = np.cos(t)
    for r in [r_sin, r_cos]:
        ax.scatter(t, r, c=r, s=t*100, edgecolor="white", cmap=plt.cm.magma_r)
        ax.scatter(t, -r, c=r, s=t*100, edgecolor="white", cmap=plt.cm.magma_r)
    ax.set_title("polar={}".format(polar),fontsize=15)
    ax.set_xticklabels([])
    return fig, ax, t

# Rectilinear
fig, ax, t = synthesize(polar=False)
# Here are the plot dimensions in response to the answer below
xlim = ax.get_xlim()
ylim = ax.get_ylim()
rlim = (ax.get_rmin(), ax.get_rmax())
print(xlim, ylim, rlim)
(0.0, 6.283185307179586) (0.0, 2.2437621373846617) (0.0, 2.2437621373846617)
# Encircling axis
divider = make_axes_locatable(ax)
ax_below = divider.append_axes("bottom", size="32.8%", pad=0.1)
ax_below.scatter(t, np.tan(t), c="black", edgecolor="white")

# Polar
fig, ax, t = synthesize(polar=True)
divider = make_axes_locatable(ax)
ax_below = divider.append_axes("bottom", size="32.8%", pad=0.1)
ax_below.scatter(t, np.tan(t), c="black", edgecolor="white")

Answer 1

您可能可以通过调整set_rmax和set_rorigin这样做：

import numpy as np
import matplotlib.pyplot as plt

plt.style.use("seaborn-white")
def synthesize(polar=False):
    fig = plt.figure()
    ax = fig.add_subplot(111, polar=polar)
    ax.set_rmax(30)
    t = np.linspace(0,2*np.pi)
    r_sin = np.sin(t)
    r_cos = np.cos(t)
    for r in [r_sin, r_cos]:
        ax.scatter(t, r, c=r, s=t*100, edgecolor="white", cmap=plt.cm.magma_r)
        ax.scatter(t, -r, c=r, s=t*100, edgecolor="white", cmap=plt.cm.magma_r)
    ax.set_title("polar={}".format(polar),fontsize=15)
    ax.set_xticklabels([])
    return fig, ax, t

# Polar
fig, ax, t = synthesize(polar=True)
ax_below = fig.add_subplot(111, polar=True, frameon=True)

# ax_below = divider.append_axes("bottom", size="32.8%", pad=0.1)
ax_below.scatter(t, np.tan(t), c="black", edgecolor="white")
ax_below.set_rorigin(-75)
ax_below.set_rmin(-25)
plt.show()