pyplot：如何以人类可读的方式显式地对轴进行编号

Posted 2021-04-15

Pyplot有一个奇怪的特性，对于大数字，轴由非基数十个数字缩放，几乎不可能读取数值：

x = [49856280.352, 49860580.25, 49861011.77, 49861103.034, 49861191.295, 49862295.297, 49862311.928, 49862755.161, 49863005.142, 49863331.328, 49863795.672, 49863892.911, 49864078.203, 49864455.172, 49864628.486, 49865539.345, 49865562.414, 49865652.025, 49865860.79, 49866049.199, 49866559.841, 49866709.259, 49866976.163, 49867118.158, 49867184.515, 49867228.03, 49867703.98, 49868191.475, 49868264.993, 49868402.682, 49868547.472, 49868849.941, 49869167.486, 49869233.011, 49869388.16, 49869462.118, 49869947.616, 49869976.177, 49870146.971, 49870441.068, 49870858.267, 49870898.339, 49870966.598, 49871065.408, 49871113.361, 49871268.792, 49871332.292, 49872008.637, 49872014.321, 49872128.757, 49872276.278, 49872296.18, 49872322.098, 49872366.707, 49872370.336, 49872537.099, 49872909.555, 49872917.363, 49873131.438, 49873230.402, 49873252.129, 49873289.302, 49873382.584, 49873429.968, 49873440.124, 49873444.505, 49873507.617, 49873835.836, 49873905.902, 49873965.72, 49874080.127, 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49893717.478, 49893841.341, 49893849.407, 49893918.451, 49893929.304, 49893965.073, 49893995.907, 49894105.083, 49894113.528, 49894207.766, 49894220.283, 49894229.309, 49894287.256, 49894296.334, 49894321.153, 49894394.072, 49894410.075, 49894426.245, 49894429.549, 49894486.508, 49894569.593, 49894596.175, 49894646.893, 49894684.32, 49894706.127, 49894730.259, 49894814.007, 49894846.182, 49894921.957, 49895075.836, 49895134.196, 49895411.552, 49895467.919, 49895581.219, 49895643.126, 49895681.785, 49895715.833, 49895717.103, 49895732.304, 49895747.613, 49895775.574, 49895797.26, 49895801.342, 49895905.897, 49895914.703, 49895933.794, 49895949.521, 49895999.669, 49896017.596, 49896189.338, 49896213.562, 49896231.62, 49896310.695, 49896462.188, 49896483.7, 49896508.985, 49896602.682, 49896631.951, 49896719.268, 49896806.399, 49896806.913, 49896872.332, 49897018.727, 49897124.196, 49897134.793, 49897213.913, 49897270.838, 49897284.028, 49897315.792, 49897330.168]
plt.hist(x)
plt.show()

在我的例子中，轴应缩放1e7或1e8，或显示为rgular数字 - 而不是4.986e7。为什么有人想要这个设置？如何使x轴编号具有人类可读性？

答案

How to prevent numbers being changed to exponential form in Python matplotlib figure

ax = plt.gca()
ax.get_xaxis().get_major_formatter().set_useOffset(False)
ax.get_xaxis().get_major_formatter().set_scientific(False)
plt.draw()