问题:在matplotlib中将x轴移动到绘图的顶部
基于关于matplotlib中的热图的问题,我想将x轴标题移动到图的顶部。
import matplotlib.pyplot as plt
import numpy as np
column_labels = list('ABCD')
row_labels = list('WXYZ')
data = np.random.rand(4,4)
fig, ax = plt.subplots()
heatmap = ax.pcolor(data, cmap=plt.cm.Blues)
# put the major ticks at the middle of each cell
ax.set_xticks(np.arange(data.shape[0])+0.5, minor=False)
ax.set_yticks(np.arange(data.shape[1])+0.5, minor=False)
# want a more natural, table-like display
ax.invert_yaxis()
ax.xaxis.set_label_position('top') # <-- This doesn't work!
ax.set_xticklabels(row_labels, minor=False)
ax.set_yticklabels(column_labels, minor=False)
plt.show()
但是,调用matplotlib的set_label_position(如上所述)似乎没有达到预期的效果。这是我的输出:
我究竟做错了什么?
回答 0
用
ax.xaxis.tick_top()
将刻度线放在图像的顶部。命令
ax.set_xlabel('X LABEL')
ax.xaxis.set_label_position('top')
影响标签,而不影响刻度线。
import matplotlib.pyplot as plt
import numpy as np
column_labels = list('ABCD')
row_labels = list('WXYZ')
data = np.random.rand(4, 4)
fig, ax = plt.subplots()
heatmap = ax.pcolor(data, cmap=plt.cm.Blues)
# put the major ticks at the middle of each cell
ax.set_xticks(np.arange(data.shape[1]) + 0.5, minor=False)
ax.set_yticks(np.arange(data.shape[0]) + 0.5, minor=False)
# want a more natural, table-like display
ax.invert_yaxis()
ax.xaxis.tick_top()
ax.set_xticklabels(column_labels, minor=False)
ax.set_yticklabels(row_labels, minor=False)
plt.show()
回答 1
您想要set_ticks_position
而不是set_label_position
:
ax.xaxis.set_ticks_position('top') # the rest is the same
这给了我:
回答 2
tick_params对于设置刻度属性非常有用。可以使用以下命令将标签移到顶部:
ax.tick_params(labelbottom=False,labeltop=True)
回答 3
如果要让刻度(而不是标签)显示在顶部和底部(而不仅仅是顶部),则必须做一些额外的按摩。我可以做到的唯一方法是对unutbu的代码进行较小的更改:
import matplotlib.pyplot as plt
import numpy as np
column_labels = list('ABCD')
row_labels = list('WXYZ')
data = np.random.rand(4, 4)
fig, ax = plt.subplots()
heatmap = ax.pcolor(data, cmap=plt.cm.Blues)
# put the major ticks at the middle of each cell
ax.set_xticks(np.arange(data.shape[1]) + 0.5, minor=False)
ax.set_yticks(np.arange(data.shape[0]) + 0.5, minor=False)
# want a more natural, table-like display
ax.invert_yaxis()
ax.xaxis.tick_top()
ax.xaxis.set_ticks_position('both') # THIS IS THE ONLY CHANGE
ax.set_xticklabels(column_labels, minor=False)
ax.set_yticklabels(row_labels, minor=False)
plt.show()
输出: