<filename>vertical_bar_chart.py
ax = df.groupby('invoice_num')['day'].unique().value_counts().sort_index().plot('bar',color=color[0],figsize=(15,6))
ax.set_xlabel('Day',fontsize=15)
ax.set_ylabel('Number of Orders',fontsize=15)
ax.set_title('Number of orders for different Days',fontsize=15)
ax.set_xticklabels(('Mon','Tue','Wed','Thur','Fri','Sun'), rotation='horizontal', fontsize=15)

#-------------------------------------------------
# Annotate bar chart with percentage

# create a list to collect the plt.patches data
totals = []

# find the values and append to list
for i in ax.patches:
    totals.append(i.get_height())

# set individual bar lables using above list
total = sum(totals)

# set individual bar lables using above list
for i in ax.patches:
    # get_x pulls left or right; get_height pushes up or down
    ax.text(i.get_x()+0.1, i.get_height()+40, \
            str(round((i.get_height()/total)*100, 2))+'%', fontsize=15,
                fontweight='bold', color='red')
plt.show()
<filename>vertical_bar_chart.py
ax = df.groupby('invoice_num')['day'].unique().value_counts().sort_index().plot('bar',color=color[0],figsize=(15,6))
ax.set_xlabel('Day',fontsize=15)
ax.set_ylabel('Number of Orders',fontsize=15)
ax.set_title('Number of orders for different Days',fontsize=15)
ax.set_xticklabels(('Mon','Tue','Wed','Thur','Fri','Sun'), rotation='horizontal', fontsize=15)

#-------------------------------------------------
# Annotate bar chart with percentage

# create a list to collect the plt.patches data
totals = []

# find the values and append to list
for i in ax.patches:
    totals.append(i.get_height())

# set individual bar lables using above list
total = sum(totals)

# set individual bar lables using above list
for i in ax.patches:
    # get_x pulls left or right; get_height pushes up or down
    ax.text(i.get_x()+0.1, i.get_height()+40, \
            str(round((i.get_height()/total)*100, 2))+'%', fontsize=15,
                fontweight='bold', color='red')
plt.show()
#------------------------------------------------- # Annotate bar chart with percentage # create a list to collect the plt.patches data # find the values and append to list # set individual bar lables using above list # set individual bar lables using above list # get_x pulls left or right; get_height pushes up or down