python - 按 matplotlib 中的列表值对条形图进行排序

Question

我遇到了一个关于按价值对我的特征进行排序的问题。我希望看到我的图像，其条形图基于 y 轴上的高度而变短。不幸的是，我的条形图看起来像这样，功能按字母顺序排序：

现在我正在运行以下代码：

unsorted_list = [(importance, feature) for feature, importance in 
                  zip(features, importances)]
sorted_list = sorted(unsorted_list)

features_sorted = []
importance_sorted = []

for i in sorted_list:
    features_sorted += [i[1]]
    importance_sorted += [i[0]]

plt.title("Feature importance", fontsize=15)
plt.xlabel("Importance", fontsize=13)

plt.barh(features_sorted,importance_sorted, color="green", edgecolor='green')

# plt.savefig('importance_barh.png', dpi=100)

这是通过那里的数据：

unsorted_list =  
 [('HR', 0.28804817462980353),
 ('BR', 0.04062328177704225),
 ('Posture', 0.09011618483921582),
 ('Activity', 0.0017821837085763366),
 ('PeakAccel', 0.002649111136700579),
 ('HRV', 0.13598729040097057),
 ('ROGState', 0.014534726412631642),
 ('ROGTime', 0.22986192060475388),
 ('VerticalMin', 0.016099772399198357),
 ('VerticalPeak', 0.012697214182994502),
 ('LateralMin', 0.029479112475744584),
 ('LateralPeak', 0.022745210003295983),
 ('SagittalMin', 0.08653071485979484),
 ('SagittalPeak', 0.028845102569277088)]

sorted_list = 
[(0.0017821837085763366, 'Activity'),
 (0.002649111136700579, 'PeakAccel'),
 (0.012697214182994502, 'VerticalPeak'),
 (0.014534726412631642, 'ROGState'),
 (0.016099772399198357, 'VerticalMin'),
 (0.022745210003295983, 'LateralPeak'),
 (0.028845102569277088, 'SagittalPeak'),
 (0.029479112475744584, 'LateralMin'),
 (0.04062328177704225, 'BR'),
 (0.08653071485979484, 'SagittalMin'),
 (0.09011618483921582, 'Posture'),
 (0.13598729040097057, 'HRV'),
 (0.22986192060475388, 'ROGTime'),
 (0.28804817462980353, 'HR')]

我最近升级到 matplotlib 3.0.2

提前感谢您帮助我！

标签： pythonmatplotlib

Answer 1

编辑（基于评论）

您的代码运行良好，matplotlib 2.2.2问题似乎与您的列表命名约定以及它们之间的一些混淆。它将在 3.0.2 上按预期工作。不过，您可能有兴趣了解解决方法

features_sorted = []
importance_sorted = []

for i in sorted_list:
    features_sorted += [i[1]]
    importance_sorted += [i[0]]

plt.title("Feature importance", fontsize=15)
plt.xlabel("Importance", fontsize=13)

plt.barh(range(len(importance_sorted)), importance_sorted, color="green", edgecolor='green')
plt.yticks(range(len(importance_sorted)), features_sorted);

@tmdavison 建议的替代方案

plt.barh(range(len(importance_sorted)), importance_sorted, color="green", 
     edgecolor='green', tick_label=features_sorted)