我正在使用Python进行一些数据分析,并且正在使用Seaborn进行可视化。Seaborn对于创建热图非常有用。
我试图在我的热图上为每列的下划线加下划线。
我能够通过将它们设为italic和bold来正确突出显示最大单元格中的文本。不过,我仍然没有办法强调它。
这是我的代码示例:
data_matrix = < extract my data and put them into a matrix >
max_in_each_column = np.max(data_matrix, axis=0)
sns.heatmap(data_matrix,
mask=data_matrix == max_in_each_column,
linewidth=0.5,
annot=True,
xticklabels=my_x_tick_labels,
yticklabels=my_y_tick_labels,
cmap="coolwarm_r")
sns.heatmap(data_matrix,
mask=data_matrix != max_in_each_column,
annot_kws={"style": "italic", "weight": "bold"},
linewidth=0.5,
annot=True,
xticklabels=my_x_tick_labels,
yticklabels=my_y_tick_labels,
cbar=False,
cmap="coolwarm_r")
当然,我尝试使用参数annot_kws={"style": "underlined"}
,但是显然在Seaborn中,“样式”键仅支持“正常”,“斜体”或“斜”值。
是否有解决方法?
是的,您可以在文本中使用tex命令来解决问题。基本思想是使用annot
的seaborn.heatmap
键将字符串数组分配为文本标签。这些包含您的数据值+一些tex前缀/后缀,以允许tex使它们变为粗体/强调(斜体)/下划线或任何形式。
示例(带有随机数):
# random data
data_matrix = np.round(np.random.rand(10, 10), decimals=2)
max_in_each_column = np.max(data_matrix, axis=0)
# Activating tex in all labels globally
plt.rc('text', usetex=True)
# Adjust font specs as desired (here: closest similarity to seaborn standard
plt.rc('font', **{'size': 14.0})
plt.rc('text.latex', preamble=r'\usepackage{lmodern}')
# remains unchanged
sns.heatmap(data_matrix,
mask=data_matrix == max_in_each_column,
linewidth=0.5,
annot=True,
cmap="coolwarm_r")
# changes here
sns.heatmap(data_matrix,
mask=data_matrix != max_in_each_column,
linewidth=0.5,
# Use annot key with np.array as value containing strings of data + latex
# prefixes/suffices making the bold/italic/underline formatting
annot=np.array([r'\textbf{\emph{\underline{' + str(data) + '}}}'
for data in data_matrix.ravel()]).reshape(np.shape(data_matrix)),
# fmt key must be empty, formatting error otherwise
fmt='',
cbar=False,
cmap="coolwarm_r")
plt.show()
进一步解释注释数组:
# For all matrix_elements in your 2D data array (2D requires the .ravel() and .reshape()
# stuff at the end) construct in sum a 2D data array consisting of strings
# \textbf{\emph{\underline{<matrix_element>}}}. Each string will be represented by tex as a bold,
# italic and underlined representation of the matrix_element
np.array([r'\textbf{\emph{\underline{' + str(data) + '}}}'
for data in data_matrix.ravel()]).reshape(np.shape(data_matrix))
生成的图基本上就是您想要的: