使用for循环matplotlib绘制图例

Question

我试图用for循环绘制多行，但我想为每行创建一个单独的图例。每条线都代表“拉布拉多海”等位置，但是当我尝试绘制每条线的图例时，只有第一个“拉布拉多海”可见 如何使每行的matplotlib图成为具有可自定义标签的图例？

这是我到目前为止的代码：

fig,ax=plt.subplots()

lines = []

for i in [26,27,28,39,30,32,84,86,87,88,96,98,99]:
    lines = ax.plot(years, mov_ave(fwf_tot.where(ds.ocean_basins == i).resample(TIME='1AS').sum().sum(dim=('X','Y')),5,'edges'))

#plt.title('Total FWF anomalies per ocean basin (moving average)')
ax.legend(lines[:13], ['Labrador sea','Hudson strait','Davis strait','Baffin bay', 'Lincoln sea', 'Irish sea and St. George', 'Arctic ocean', 'Barentsz sea', 'Greenland sea',
      'North sea', 'Kategat', 'Skagerrak', 'Norwegian sea'],loc='upper left');
plt.grid()
plt.show()

Answer 1

您要在每个情节之后重新定义lines。也许你想要

lines = []

for i in [26,27,28,39,30,32,84,86,87,88,96,98,99]:
    line = ax.plot(years, mov_ave(fwf_tot.where(ds.ocean_basins == i).resample(TIME='1AS').sum().sum(dim=('X','Y')),5,'edges'))
    # add the line to line list
    lines.append(line)

ax.legend(lines, ....)

但是，我认为将标签传递到ax.plot会更清洁：

labels = ['Labrador sea','Hudson strait','Davis strait','Baffin bay', 'Lincoln sea', 'Irish sea and St. George', 'Arctic ocean', 'Barentsz sea', 'Greenland sea',
      'North sea', 'Kategat', 'Skagerrak', 'Norwegian sea']

values = [26,27,28,39,30,32,84,86,87,88,96,98,99]
for i,l in zip(values, labels):
    lines = ax.plot(years, mov_ave(fwf_tot.where(ds.ocean_basins == i)
                                          .resample(TIME='1AS').sum()
                                          .sum(dim=('X','Y')),
                                   5,'edges'),
                    label=l)

plt.title('Total FWF anomalies per ocean basin (moving average)')

ax.legend()
plt.grid()
plt.show()