MWE

Question

我正在尝试从matplotlib.patches.RegularPolygon派生一个班级。目前的目标是为matplotlib.patches.Circle和matplotlib.patches.RegularPolygon设置一个统一的API（它们的某些属性不同），然后我可以在我的应用程序的其余部分中使用它。由于到目前为止所有代码都是为Circle编写的，因此修改RegularPolygon的属性是有意义的。

但是，出于某种原因，参数没有正确传递 - 至少到目前为止这是我最好的解释。我可以使用一些指针为什么会这样。我已经盯着源代码（link）了很长时间而没有看到它（可能是因为我看错了地方）。

MWE

import matplotlib

class RegularPolygon(matplotlib.patches.RegularPolygon):
    def __init__(self, *args, **kwargs):
        super(matplotlib.patches.RegularPolygon, self).__init__(*args, **kwargs)

RegularPolygon((0.,0.), 5, radius=5, orientation=0)

错误消息

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-4-1189a0acbaf3> in <module>()
----> 1 RegularPolygon((0.,0.), 5, radius=5, orientation=0)

<ipython-input-3-3cc2c77e24bf> in __init__(self, *args, **kwargs)
      6
      7     def __init__(self, *args, **kwargs):
----> 8         super(matplotlib.patches.RegularPolygon, self).__init__(*args, **kwargs)

/home/paul/.virtualenvs/base2/local/lib/python2.7/site-packages/matplotlib/patches.pyc in __init__(self, edgecolor, facecolor, color, linewidth, linestyle, antialiased, hatch, fill, capstyle, joinstyle, **kwargs)
     93             self.set_color(color)
     94         else:
---> 95             self.set_edgecolor(edgecolor)
     96             self.set_facecolor(facecolor)
     97         # unscaled dashes.  Needed to scale dash patterns by lw

/home/paul/.virtualenvs/base2/local/lib/python2.7/site-packages/matplotlib/patches.pyc in set_edgecolor(self, color)
    282         """
    283         self._original_edgecolor = color
--> 284         self._set_edgecolor(color)
    285
    286     def set_ec(self, color):

/home/paul/.virtualenvs/base2/local/lib/python2.7/site-packages/matplotlib/patches.pyc in _set_edgecolor(self, color)
    270                 set_hatch_color = False
    271
--> 272         self._edgecolor = colors.to_rgba(color, self._alpha)
    273         if set_hatch_color:
    274             self._hatch_color = self._edgecolor

/home/paul/.virtualenvs/base2/local/lib/python2.7/site-packages/matplotlib/colors.pyc in to_rgba(c, alpha)
    132         rgba = _colors_full_map.cache[c, alpha]
    133     except (KeyError, TypeError):  # Not in cache, or unhashable.
--> 134         rgba = _to_rgba_no_colorcycle(c, alpha)
    135         try:
    136             _colors_full_map.cache[c, alpha] = rgba

/home/paul/.virtualenvs/base2/local/lib/python2.7/site-packages/matplotlib/colors.pyc in _to_rgba_no_colorcycle(c, alpha)
    187     c = tuple(c.astype(float))
    188     if len(c) not in [3, 4]:
--> 189         raise ValueError("RGBA sequence should have length 3 or 4")
    190     if len(c) == 3 and alpha is None:
    191         alpha = 1

ValueError: RGBA sequence should have length 3 or 4

Answer 1

使用

super(matplotlib.patches.RegularPolygon, self).__init__()

你调用matplotlib.patches.RegularPolygon父项的init函数。但是你真的需要调用matplotlib.patches.RegularPolygon本身的init。

我还建议不要为子类艺术家使用相同的名称，因为这可能会增加混淆。

您拥有的选项

旧式

import matplotlib

class MyRegularPolygon(matplotlib.patches.RegularPolygon):
    def __init__(self, *args, **kwargs):
        matplotlib.patches.RegularPolygon.__init__(self, *args, **kwargs)

r = MyRegularPolygon((0.,0.), 5, radius=5, orientation=0)

新风格（py2＆amp; 3）

import matplotlib

class MyRegularPolygon(matplotlib.patches.RegularPolygon):
    def __init__(self, *args, **kwargs):
        super(MyRegularPolygon, self).__init__(*args, **kwargs)

r = MyRegularPolygon((0.,0.), 5, radius=5, orientation=0)

新风格（仅限py3）

import matplotlib

class MyRegularPolygon(matplotlib.patches.RegularPolygon):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

r = MyRegularPolygon((0.,0.), 5, radius=5, orientation=0)

我建议您阅读What does 'super' do in Python?，了解super的一些解释。

继承自`matplotlib.patches.RegularPolygon`会在实例化

MWE

错误消息

1 个答案: