figtext datetime function matplotlib

Question

我想在matplotlib的图形中创建一个文本框，它给了我创建图形的日期。

我已经使用matplotlib中的figtext函数在图形的右下角创建了一个文本框，但无法弄清楚如何在文本框中包含python datetime函数以显示日期。有任何想法吗？

代码和图形如下：

#Stacked Bar Char- matplotlib 
#Create the general blog and the "subplots" i.e. the bars 
f, ax1 = plt.subplots(1, figsize=(8,5), dpi=1000) 
# Set the bar width 
bar_width = 0.50 
# positions of the left bar-boundaries 
bar_l = [i+1 for i in range(len(df4['Pandas']))] 
# positions of the x-axis ticks (center of the bars as bar labels) 
tick_pos = [i+(bar_width/2) for i in bar_l] 

#Stack the negative bars by region 
#Start bottom at 0, and then use pandas to add bars together 
ax1.bar(bar_l, df4['cats1'], width=bar_width, label='cats',color='R', alpha=.4, align='center', 
     bottom = 0) 
ax1.bar(bar_l, df4['dogs1'], width=bar_width,label='dogs',color='#ADD8E6',alpha=.4, fill=True, align='center', 
     bottom =(df4['cats1'])) 
ax1.bar(bar_l, df4['zebras1'], width=bar_width, label='zebras',color='#FFA500',alpha=.4, align='center', 
     bottom = np.array(df4['cats1'])+np.array(df4['dogs1'])) 
ax1.bar(bar_l, df4['pandas1'], width=bar_width, label='pandas', color='b',alpha=.5, fill=True, align='center', 
     bottom = np.array(df4['cats1'])+np.array(df4['dogs1'])+np.array(df4['zebras1'])) 
#Stack the positive bars by region 
#Start bottom at 0, and then use pandas to add bars together 
ax1.bar(bar_l, df4['cats'], width=bar_width,color='R', alpha=.4, align='center', 
     bottom = 0) 
ax1.bar(bar_l, df4['dogs'], width=bar_width,color='#ADD8E6',alpha=.4, fill=True, align='center', 
     bottom =(df4['cats'])) 
ax1.bar(bar_l, df4['zebras'], width=bar_width ,color='#FFA500',alpha=.4, align='center', 
     bottom = np.array(df4['cats'])+np.array(df4['dogs'])) 
ax1.bar(bar_l, df4['pandas'], width=bar_width, color='b',alpha=.5, fill=True, align='center', 
     bottom = np.array(df4['cats'])+np.array(df4['dogs'])+np.array(df4['zebras'])) 

# set the x ticks with names 
plt.xticks(tick_pos, df4['Year'],fontsize=10) 


# Set the label and legends 
plt.title('Animals on the farm', fontweight='bold') 
ax1.set_ylim([-1600,1000]) 
ax1.set_ylabel("Count",fontsize=12) 
ax1.set_xlabel("Year",fontsize=12) 
plt.legend(loc='upper left', prop={'size':6}) 
ax1.axhline(y=0, color='k') 
ax1.axvline(x=0, color='k') 
plt.figtext(0, 0,"Data as of ", wrap=False, 
      horizontalalignment='left',verticalalignment ='bottom', fontsize=8) 
plt.setp(ax1.get_yticklabels(), rotation='horizontal', fontsize=10) 
plt.show() 

Graph= Animals on the Farm

Answer 1

下面是今天的日期的例子：

import datetime as dt 

plt.figtext(0, 0,"Data as of {}".format(dt.date.today().strftime('%Y-%m-%d')), wrap=False, 
      horizontalalignment='left',verticalalignment ='bottom', fontsize=8) 

Answer 2

如果你有一个datetime对象，你可以使用strftime方法来转换它使用你想要的格式的字符串表示形式：

from datetime import datetime 
plt.figtext(0, 0, 'Date as of ' + datetime.now().strftime('%Y-%m-%d'))