正如WillZ所指出的那样,Pandas 0.21破坏了unutbu的解决方法。然而,将日期时间转换为日期可能会对数据分析产生显著的负面影响。这个解决方案目前可以工作并保留日期时间:
import numpy as np
import matplotlib.pyplot as plt
import pandas as pd
N = 300
dates = pd.date_range('2000-1-1', periods=N, freq='ms')
x = np.linspace(0, 2*np.pi, N)
data = pd.DataFrame({'A': np.sin(x), 'B': np.cos(x),
'Date': dates})
d = data['Date'].dt.to_pydatetime()
plt.plot_date(d, data['A'], '-')
plt.plot_date(d, data['B'], '-')
plt.fill_between(d, data['A'], data['B'],
where=data['A'] >= data['B'],
facecolor='green', alpha=0.2, interpolate=True)
plt.xticks(rotation=25)
plt.show()
![使用datetime64限制的fill_between](https://istack.dev59.com/DNP6o.webp)
编辑:根据jedi的评论,我试图确定以下三个选项中最快的方法:
- method1 = 原始答案
- method2 = jedi的评论 + 原始答案
- method3 = jedi的评论
method2稍微快一些,但更加稳定,因此我已编辑上面的答案以反映最佳方法。
import numpy as np
import matplotlib.pyplot as plt
import pandas as pd
import time
N = 300
dates = pd.date_range('2000-1-1', periods=N, freq='ms')
x = np.linspace(0, 2*np.pi, N)
data = pd.DataFrame({'A': np.sin(x), 'B': np.cos(x),
'Date': dates})
time_data = pd.DataFrame(columns=['1', '2', '3', '4', '5', '6', '7', '8', '9', '10'])
method1 = []
method2 = []
method3 = []
for i in range(0, 10):
start = time.clock()
for i in range(0, 500):
d = [pd.Timestamp(x).to_pydatetime() for x in data['Date']]
plt.plot_date(d, data['A'], '-')
plt.plot_date(d, data['B'], '-')
plt.fill_between(d, data['A'], data['B'],
where=data['A'] >= data['B'],
facecolor='green', alpha=0.2, interpolate=True)
plt.xticks(rotation=25)
plt.gcf().clear()
method1.append(time.clock() - start)
for i in range(0, 10):
start = time.clock()
for i in range(0, 500):
d = data['Date'].dt.to_pydatetime()
plt.plot_date(d, data['A'], '-')
plt.plot_date(d, data['B'], '-')
plt.fill_between(d, data['A'], data['B'],
where=data['A'] >= data['B'],
facecolor='green', alpha=0.2, interpolate=True)
plt.xticks(rotation=25)
plt.gcf().clear()
method2.append(time.clock() - start)
for i in range(0, 10):
start = time.clock()
for i in range(0, 500):
plt.plot_date(data['Date'].dt.to_pydatetime(), data['A'], '-')
plt.plot_date(data['Date'].dt.to_pydatetime(), data['B'], '-')
plt.fill_between(data['Date'].dt.to_pydatetime(), data['A'], data['B'],
where=data['A'] >= data['B'],
facecolor='green', alpha=0.2, interpolate=True)
plt.xticks(rotation=25)
plt.gcf().clear()
method3.append(time.clock() - start)
time_data.loc['method1'] = method1
time_data.loc['method2'] = method2
time_data.loc['method3'] = method3
print(time_data)
plt.errorbar(time_data.index, time_data.mean(axis=1), yerr=time_data.std(axis=1))
![time test of 3 methods on converting time data for plotting a DataFrame](https://istack.dev59.com/IZWZE.webp)
plt
和轴plt.fill_between( data['Date'].dt.to_pydatetime(), data['A'],...
。它将 numpy datetime64[ns] 转换为 fill_between 可以理解的 python datetime。 - jedi