图 matplotlib 上的 2 个图例

Question

我想为不同的模型绘制多条曲线。我有不同结构的曲线。结构需要具有相同的颜色，不同的模型需要不同的线型。然后我想要 2 个图例，一个具有与结构相对应的颜色，另一个具有线条样式。这是我已经拥有的代码：

谢谢！！！

plt.figure(figsize=(12,8))

styles = ['-', '--']
colors = ['blue', 'orange', 'green', 'red', 'purple', 'brown', 'pink', 'grey']


plans = ['Clinical', 'AP']

for j, plan in enumerate(plans):

    for i, structure in enumerate(structures_dvh):
    # for i, structure in enumerate(structure_test):

        if plan == 'Clinical':

            mean_dose, mean_volume = compute_mean_dvh(Lung_R2_adap, structure)
            plt.plot(mean_dose, mean_volume, label = structure, c = colors[i], ls = styles[j])

        elif plan == 'AP':
           
            mean_dose, mean_volume = compute_mean_dvh(Lung_AP, structure)
            plt.plot(mean_dose, mean_volume, c = colors[i], ls = styles[j])

        elif plan == 'PS':

            mean_dose, mean_volume = compute_mean_dvh(Lung_PS, structure)
            plt.plot(mean_dose, mean_volume, c = colors[i], ls = styles[j])

# plt.legend(handles = linestyle_legend_handles, loc = 'lower left')
plt.legend(loc = 'lower center', bbox_to_anchor=(0.5, -0.25), fancybox=True, shadow=True, ncol=3)

plt.title('Mean DVH')
plt.xlabel('Relative dose')
plt.ylabel('Volume [%]')
plt.grid(True)
plt.tight_layout()

plt.show()

Answer 1

有多种方法可以解决这个问题（例如，参见matplotlib：同一图表上的2个不同图例和这个Matplotlib示例），但这里有一个基本示例：

from matplotlib import pyplot as plt
import numpy as np

plans = ["Clinical", "AP"]
structures = ["A", "B"]

colours = ["blue", "orange"]
styles = ["-", "--"]

# dictionary to store all your plotted lines
lines = {p: [] for p in plans}

fig, ax = plt.subplots()

N = 10
x = np.linspace(0, 1, N)

for j, plan in enumerate(plans):
    for i, structure in enumerate(structures):
        # plot some fake data
        l, = ax.plot(x, np.random.randn(N) + j * 2 + i, color=colours[i], ls=styles[j])

        # append the plotted lines
        lines[plan].append(l)

locs = ["upper left", "upper right"]

# create legend for each plan (I've put the plan name as a title for the legend)
for i, plan in enumerate(plans):
    leg = ax.legend(lines[plan], structures, title=plan, loc=locs[i])
    ax.add_artist(leg)