Python matplotlib轴格式

我正在matplotlib中创建一个实时绘图，hpwever我无法让x轴实时更新刻度，我想做的是获得每个刻度的发生时间，例如，如果将刻度设置为5分钟间隔，则它将是

10:20、10:25、10:30等

。我当前所做的不起作用，我将新时间附加到数组中，然后将数组调用到xtick。 数组：

xticks：

self.ax1.set_xticklabels(self.date)

---

如果这对你有意义，请告诉我。我把这个例子放在一起，它不是最漂亮的。我认为关键是使用绘图时间（ars…）告诉matplotlib正确查找数字和格式

使用python[2.7.2]，matplotlib，numpy：

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

tWindow=1 #moving window in minutes

timeList=[datetime.now()]
valList=[random.randint(1, 20)]

fig = plt.figure() #Make a figure
ax = fig.add_subplot(111) #Add a subplot

#Create the line with initial data using plot_date to add time to the x axis
line,=plt.plot_date(timeList, valList, linestyle='-') 

#Set the x limits to the time window
ax.set_xlim([datetime.now()-timedelta(seconds=tWindow*60),datetime.now()])

#set the y limits
ax.set_ylim(0,20)

#grab the blank background to clear the plot later
background = fig.canvas.copy_from_bbox(ax.bbox)

#show the figure
fig.show()

#loop
for i in range(100):
    #restore the background
    fig.canvas.restore_region(background)

    #add time to time list
    timeList.append(datetime.now())

    #add random value to values
    valList.append(random.randint(1, 20))

    #update the line data
    line.set_data(timeList,valList)

    #update x limits
    ax.set_xlim([datetime.now()-timedelta(seconds=tWindow*60),datetime.now()])

    #redraw widnow
    fig.canvas.draw()

    #pause the loop for .5 seconds
    time.sleep(0.5)

产生：

更新： 我刚刚找到了你的另一个密码，我猜你正在使用

试着替换

self.l_user, = self.ax.plot([],self.user, label='Total %')

与

现在，您可以将时间戳传递给matplotlib，而不是

def timerEvent(self, evt):
        # get the cpu percentage usage
        result = self.get_cpu_usage()
        # append new data to the datasets
        self.user.append(result[0])
        # update lines data using the lists with new data
        self.l_user.set_data(range(len(self.user)), self.user)
        # force a redraw of the Figure
        self.fig.canvas.draw()
           #else, we increment the counter
        self.cnt += 1

试着做一些类似的事情

def timerEvent(self, evt):
        # get the cpu percentage usage
        result = self.get_cpu_usage()
        # append new data to the datasets
        self.user.append(result[0])
        #save the current time
        self.timeStamp.append(datetime.now())
        # update lines data using the lists with new data
        self.l_user.set_data(self.timeStamp, self.user)
        #rescale the x axis maintaining a 5 minutes window
        self.ax.set_xlim([datetime.now()-timedelta(seconds=5*60),datetime.now()])
        # force a redraw of the Figure, this might not update the x axis limits??
        self.fig.canvas.draw()
           #else, we increment the counter
        self.cnt += 1

通过适当的导入和变量初始化

from datetime import datetime, timedelta

class CPUMonitor(FigureCanvas):
    """Matplotlib Figure widget to display CPU utilization"""
    def __init__(self):
        ...
        self.timeStamp=[]
        ...

---

你必须更改XTICK还是可以重新缩放轴？我必须更改XTICK，因为轴是实时的。也许我不理解这个问题。您试图绘制什么（即数据看起来像什么）？您是否试图创建一个仅显示5分钟窗口的“滚动”绘图？最后，据我所知，

setxticklabels

只会更改文本标签，而不会更改x轴比例。我拥有的是一个实时绘图，它会一直持续到用户退出程序，绘图是一个线条图，如果您是windows，请查看任务管理器/性能，我的绘图与他们的，除了我想在xticks上加上时间，所以基本上你想要一个在x轴上有一定时间范围的移动图？我将尝试组合一些内容。@user1582983，这样我上面发布的代码就可以在我的机器上运行（windows、python 2.7.2、matplotlib等）。那么，你有什么不同的做法？（顺便说一句，你提供的细节越多，你的回答就越好）它给了我一个错误，

dt=datetime.datetime.fromordinal（ix）ValueError:ordinal必须>=1

@user1582983，欢迎你，我很高兴它能工作！y轴是否随时间改变比例？我不确定self.fig.canvas.draw（）是否也会更新它。

def timerEvent(self, evt):
        # get the cpu percentage usage
        result = self.get_cpu_usage()
        # append new data to the datasets
        self.user.append(result[0])
        #save the current time
        self.timeStamp.append(datetime.now())
        # update lines data using the lists with new data
        self.l_user.set_data(self.timeStamp, self.user)
        #rescale the x axis maintaining a 5 minutes window
        self.ax.set_xlim([datetime.now()-timedelta(seconds=5*60),datetime.now()])
        # force a redraw of the Figure, this might not update the x axis limits??
        self.fig.canvas.draw()
           #else, we increment the counter
        self.cnt += 1

from datetime import datetime, timedelta

class CPUMonitor(FigureCanvas):
    """Matplotlib Figure widget to display CPU utilization"""
    def __init__(self):
        ...
        self.timeStamp=[]
        ...