如何在matplotlib中更改轴标签的格式

Question

如果我绘制数刻度图,matplotlib给我好看的条目10 ⁵,10 ⁶,...

为了便于阅读,我宁愿选择1e5,1e6,......

我可以直接设置轴属性以表现那样吗？

我相当丑陋的黑客将是:

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(1, 40, 100);
y = np.linspace(1, 5, 100);

# Actually plot the exponential values
plt.plot(x, 10**y)
ax = plt.gca()
ax.set_yscale('log')

# Rewrite the y labels
y_labels = ax.get_yticks()
ax.set_yticklabels(['1e%i' % np.round(np.log(y)/np.log(10)) for y in y_labels])

plt.show()

但肯定有一个更好的方法.

Answer 1

你用ticker.FormatStrFormatter('%0.0e').这将%0.0e使用表示浮点数的字符串格式格式化每个数字,使用指数表示法:

import numpy as np
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker

x = np.linspace(1, 40, 100)
y = np.linspace(1, 5, 100)

# Actually plot the exponential values
fig, ax = plt.subplots()
ax.plot(x, 10**y)
ax.set_yscale('log')

# Rewrite the y labels
y_labels = ax.get_yticks()
ax.yaxis.set_major_formatter(ticker.FormatStrFormatter('%0.0e'))

plt.show()

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