matplotlib & pandas

Python/matplotlab/gallery/mplot3d/pathpatch3d.md

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+# 在3D绘图中绘制平面对象
+
+演示如何使用pathpatch_2d_to_3d在3D绘图上“绘制”形状和文本。
+
+![在3D绘图中绘制平面对象示例](https://matplotlib.org/_images/sphx_glr_pathpatch3d_001.png)
+
+```python
+import numpy as np
+import matplotlib.pyplot as plt
+from matplotlib.patches import Circle, PathPatch
+from matplotlib.text import TextPath
+from matplotlib.transforms import Affine2D
+# This import registers the 3D projection, but is otherwise unused.
+from mpl_toolkits.mplot3d import Axes3D  # noqa: F401 unused import
+import mpl_toolkits.mplot3d.art3d as art3d
+
+
+def text3d(ax, xyz, s, zdir="z", size=None, angle=0, usetex=False, **kwargs):
+    '''
+    Plots the string 's' on the axes 'ax', with position 'xyz', size 'size',
+    and rotation angle 'angle'.  'zdir' gives the axis which is to be treated
+    as the third dimension.  usetex is a boolean indicating whether the string
+    should be interpreted as latex or not.  Any additional keyword arguments
+    are passed on to transform_path.
+
+    Note: zdir affects the interpretation of xyz.
+    '''
+    x, y, z = xyz
+    if zdir == "y":
+        xy1, z1 = (x, z), y
+    elif zdir == "x":
+        xy1, z1 = (y, z), x
+    else:
+        xy1, z1 = (x, y), z
+
+    text_path = TextPath((0, 0), s, size=size, usetex=usetex)
+    trans = Affine2D().rotate(angle).translate(xy1[0], xy1[1])
+
+    p1 = PathPatch(trans.transform_path(text_path), **kwargs)
+    ax.add_patch(p1)
+    art3d.pathpatch_2d_to_3d(p1, z=z1, zdir=zdir)
+
+
+fig = plt.figure()
+ax = fig.add_subplot(111, projection='3d')
+
+# Draw a circle on the x=0 'wall'
+p = Circle((5, 5), 3)
+ax.add_patch(p)
+art3d.pathpatch_2d_to_3d(p, z=0, zdir="x")
+
+# Manually label the axes
+text3d(ax, (4, -2, 0), "X-axis", zdir="z", size=.5, usetex=False,
+       ec="none", fc="k")
+text3d(ax, (12, 4, 0), "Y-axis", zdir="z", size=.5, usetex=False,
+       angle=np.pi / 2, ec="none", fc="k")
+text3d(ax, (12, 10, 4), "Z-axis", zdir="y", size=.5, usetex=False,
+       angle=np.pi / 2, ec="none", fc="k")
+
+# Write a Latex formula on the z=0 'floor'
+text3d(ax, (1, 5, 0),
+       r"$\displaystyle G_{\mu\nu} + \Lambda g_{\mu\nu} = "
+       r"\frac{8\pi G}{c^4} T_{\mu\nu}  $",
+       zdir="z", size=1, usetex=True,
+       ec="none", fc="k")
+
+ax.set_xlim(0, 10)
+ax.set_ylim(0, 10)
+ax.set_zlim(0, 10)
+
+plt.show()
+```
+
+## 下载这个示例
+            
+- [下载python源码: pathpatch3d.py](https://matplotlib.org/_downloads/pathpatch3d.py)
+- [下载Jupyter notebook: pathpatch3d.ipynb](https://matplotlib.org/_downloads/pathpatch3d.ipynb)
+