Matplotlib图在添加注释时不显示线条

Question

I am trying to figure out how matplotlib annotaitons work and I tried the following:

fig = plt.figure()
ax = fig.add_subplot(111, autoscale_on=False, ylim=(1, 9000000))

plt.plot(df['month'], df['France'], label='France')
plt.plot(df['month'], df['Germany'], label='Germany')

ax.annotate('test', xy=(100, 1000), xytext=(3, 1.5),
            arrowprops=dict(facecolor='black', shrink=0.05),
            )

fig.set_size_inches(15, 7)
plt.legend(loc=2)
plt.show()

It is giving me a plot area, but is not showing the lines or the annotations. Any thoughts?

The following works and gives me a graph, but no annotations, obviously:

fig = plt.figure()
ax = fig.add_subplot(autoscale_on=False, ylim=(1, 9000000))

plt.plot(df['month'], df['France'], label='France')
plt.plot(df['month'], df['Germany'], label='Germany')

fig.set_size_inches(15, 7)
plt.legend(loc=2)
plt.show()

Answer 1

Have you tried adding arrowstyle'='-' (or '->' , or '<-' or '<->' depending on what type of line or arrow you want) to your arrowprops dictionary? Note also that the xy coordinates should be in data units, so it may be that (100, 1000) is not within your axes area (I don't know the range of values of your data.)