seaborn 热图注释 ValueError:类型为“numpy.str_”的对象的未知格式代码“g”

Zep*_*hyr 10 python numpy matplotlib heatmap seaborn

我想绘制一个seaborn.heatmap并仅注释一些行/列。
所有单元格都有注释的示例:

import seaborn as sns
import matplotlib.pyplot as plt
import numpy as np


n1 = 5
n2 = 10
M = np.random.random((n1, n2))   

fig, ax = plt.subplots()

sns.heatmap(ax = ax, data = M, annot = True)

plt.show()
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在此输入图像描述

按照这些示例添加值注释段落),可以将seaborn.heatmap每个单元格的注释作为annot参数传递给数组:

annot :布尔或矩形数据集,可选
如果为 True,则在每个单元格中写入数据值。如果是与数据具有相同形状的类似数组,则使用它来注释热图而不是数据。请注意,DataFrame 将匹配位置,而不是索引。

如果我尝试生成一个数组str并将其作为annot参数传递给,seaborn.heatmap我会收到以下错误:

Traceback (most recent call last):
  File "C:/.../myfile.py", line 16, in <module>
    sns.heatmap(ax = ax, data = M, annot = A)
  File "C:\venv\lib\site-packages\seaborn\_decorators.py", line 46, in inner_f
    return f(**kwargs)
  File "C:\venv\lib\site-packages\seaborn\matrix.py", line 558, in heatmap
    plotter.plot(ax, cbar_ax, kwargs)
  File "C:\venv\lib\site-packages\seaborn\matrix.py", line 353, in plot
    self._annotate_heatmap(ax, mesh)
  File "C:\venv\lib\site-packages\seaborn\matrix.py", line 262, in _annotate_heatmap
    annotation = ("{:" + self.fmt + "}").format(val)
ValueError: Unknown format code 'g' for object of type 'numpy.str_'
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生成的代码ValueError(在本例中,我尝试删除第四列的注释作为示例):

import seaborn as sns
import matplotlib.pyplot as plt
import numpy as np


n1 = 5
n2 = 10
M = np.random.random((n1, n2))

A = np.array([[f'{M[i, j]:.2f}' for j in range(n2)] for i in range(n1)])
A[:, 3] = ''


fig, ax = plt.subplots(figsize = (6, 3))

sns.heatmap(ax = ax, data = M, annot = A)

plt.show()
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出现这个错误的原因是什么?
如何生成seaborn.heatmap并仅注释选定的行/列?

Rox*_*oxy 13

这是一个格式问题。fmt = ''如果您使用non-numeric标签(默认为:) ,则此处是必需的fmt='.2g',该标签仅考虑数值并对文本格式的标签引发错误。

import seaborn as sns
import matplotlib.pyplot as plt
import numpy as np


n1 = 5
n2 = 10
M = np.random.random((n1, n2))

A = np.array([[f'{M[i, j]:.2f}' for j in range(n2)] for i in range(n1)])
A[:, 3] = ''


fig, ax = plt.subplots(figsize = (6, 3))

sns.heatmap(ax = ax, data = M, annot = A, fmt='')

plt.show()
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