如何在 matplotlib 直方图中显示刻度标签？

Question

I do not usually use Matplotlib and I am trying to graph some information in a time series histogram.

My histogram works fine when I put the data in but I cannot get it to show the xaxis tick labels.

Here is my code (using placeholder data):

import matplotlib.pyplot as plt  
import matplotlib.dates as mdates  
from matplotlib.dates import HourLocator as HourLocater  

import datetime  
from datetime import datetime  
from datetime import timedelta  

now = datetime.today()  
timecount = []  

for x in range(8):  
datea = now-timedelta(hours=x)  
    dateb = str(datea).split(':')[0]  
    timecount.append(dateb)  

fig, ax = plt.subplots(1,1)
ax.hist(timecount, bins=50, color='lightblue')
ax.xaxis.set_major_locator(HourLocater(interval=1))
ax.xaxis.set_major_formatter(mdates.DateFormatter('%Y-%m-%d %H'))
plt.show()

Answer 1

You are creating x with string,then trying to format your axis with datetimes, Let's stick with datatimes, and use just datea variable and not dateb .

import matplotlib.pyplot as plt  
import matplotlib.dates as mdates  
from matplotlib.dates import HourLocator as HourLocater  

import datetime  
from datetime import datetime  
from datetime import timedelta  

now = datetime.today()  
timecount = []  

for x in range(8):  
    datea = now-timedelta(hours=x)  
    dateb = str(datea).split(':')[0]  
    timecount.append(datea)  

fig, ax = plt.subplots(1,1)
ax.hist(timecount, bins=50, color='lightblue')
ax.xaxis.set_major_locator(HourLocater(interval=1))
ax.xaxis.set_major_formatter(mdates.DateFormatter('%Y-%m-%d %H'))
plt.xticks(rotation=90)
plt.show()

Output: