X轴绘图与Matplotlib

时间:2018-05-23 18:52:32

标签: python python-3.x matplotlib

代码运行正常,但在X axis上,日期并没有像字典中所描述的那样显示出来(它只显示在情节hours:minute:second上)。

如何显示完整日期(year:month:day hours:minute:second)?

代码:

import numpy as np
import matplotlib.pyplot as plt
import time
from datetime import datetime, timedelta

EQ = {'2017-08-23 02:04:00':(18,1),'2017-08-23 02:05:00':(20,2),'2017-08-23 02:06:00':(12,3),'2017-08-23 02:07:00':(22,4)}
LIST_P=[];Time_P=[]
for j_p in EQ.keys():
        LIST_P.append(EQ[j_p][1])
        Time_P.append(time.mktime(time.strptime(j_p, "%Y-%m-%d %H:%M:%S")))

dateconv=np.vectorize(datetime.fromtimestamp)
Date_F1=dateconv(Time_P)
fig1 = plt.figure(1)
ax1 = plt.gca()
ax1.plot_date(Date_F1,LIST_P,'g-')
ax1.set_ylabel('Y-axis',fontsize=14)
ax1.set_xlabel('X-axis',fontsize=14)
ax1.grid(True)
for label in ax1.xaxis.get_ticklabels():
    label.set_rotation(45)
plt.show()

2 个答案:

答案 0 :(得分:0)

您需要添加ax1.xaxis.set_major_formatter(mdates.DateFormatter("%Y-%m-%d %H:%M:%S"))来指定格式。 请考虑以下代码:

import numpy as np
import matplotlib.pyplot as plt
import time
from datetime import datetime, timedelta
import matplotlib.dates as mdates

EQ = {'2017-08-23 02:04:00':(18,1),'2017-08-23 02:05:00':(20,2),'2017-08-23 02:06:00':(12,3),'2017-08-23 02:07:00':(22,4)}
LIST_P=[];Time_P=[]
for j_p in EQ.keys():
        LIST_P.append(EQ[j_p][1])
        Time_P.append(time.mktime(time.strptime(j_p, "%Y-%m-%d %H:%M:%S")))

dateconv=np.vectorize(datetime.fromtimestamp)
Date_F1=dateconv(Time_P)
fig1 = plt.figure(1)
ax1 = plt.gca()
ax1.xaxis.set_major_formatter(mdates.DateFormatter("%Y-%m-%d %H:%M:%S"))
ax1.plot_date(Date_F1,LIST_P,'g-')
ax1.set_ylabel('Y-axis',fontsize=14)
ax1.set_xlabel('X-axis',fontsize=14)
ax1.grid(True)
for label in ax1.xaxis.get_ticklabels():
    label.set_rotation(45)
plt.show()

输出:

enter image description here

答案 1 :(得分:-1)

我建议使用matplotlib.dates的DateFormatter,添加以下内容:

1)一开始: 来自matplotlib.dates导入DateFormatter

2)在ax1.plot_date之前: myFmt = DateFormatter("%Y-%m-%d%H:%M:%S") ax1.xaxis.set_major_formatter(myFmt)