Python 条形图 plot y轴显示百分比

Question

I have plotted a bar plot. I want the yaxis display values in percentage.

My code:

import matplotlib.ticker as mtick

df = 
     name    qty
0    Aple    200
1    Bana    67
2    Oran    10
3    Mang    8

ax=plt.bar(df['name'],df['qty'])
ax.yaxis.set_major_formatter(mtick.PercentFormatter())
plt.show()

Present output:

ax.yaxis.set_major_formatter(mtick.PercentFormatter())

AttributeError: 'BarContainer' object has no attribute 'yaxis'

Answer 1

plt.bar does not return the axis instance. I think you mean:

ax = df.plot.bar(x='name',y='qty')
ax.yaxis.set_major_formatter(mtick.PercentFormatter())

Or

fig, ax = plt.subplots()

ax.bar(df['name'],df['qty'])
ax.yaxis.set_major_formatter(mtick.PercentFormatter())

Output:

However, guessing from you trying to plot percentage , I think you want:

fig, ax = plt.subplots()

# note the division here
ax.bar(df['name'],df['qty']/df['qty'].sum())
ax.yaxis.set_major_formatter(mtick.PercentFormatter())

Output: