python画桑基图代码

以下是使用Python的matplotlib库画桑基图的示例代码：

import matplotlib.pyplot as plt

# 数据准备
labels = ['A', 'B', 'C', 'D', 'E', 'F']
values = [10, 15, 20, 25, 30, 35]
flows = [5, 10, -5, -15, 10, 10]

# 计算节点位置和大小
positions = range(len(labels))
sizes = [v/sum(values) for v in values]

# 绘制桑基图
fig, ax = plt.subplots()
ax.axis('off')
ax.set_xlim(-1, 1)
ax.set_ylim(-1, 1)
ax.invert_yaxis()

for i in positions:
    ax.add_patch(plt.Circle((0, i), sizes[i], color='lightgrey'))
    
for i in range(len(flows)):
    if flows[i] > 0:
        ax.arrow(-0.1, i, 0.2, 0, head_width=0.05, head_length=0.1, fc='blue', ec='blue')
        ax.arrow(0.1, i, 0.7, 0, head_width=0.05, head_length=0.1, fc='red', ec='red')
        ax.text(0, i, str(flows[i]), ha='center', va='center', color='white')
    elif flows[i] < 0:
        ax.arrow(0.1, i, -0.2, 0, head_width=0.05, head_length=0.1, fc='blue', ec='blue')
        ax.arrow(-0.1, i, -0.7, 0, head_width=0.05, head_length=0.1, fc='red', ec='red')
        ax.text(0, i, str(-flows[i]), ha='center', va='center', color='white')

for i in positions:
    ax.text(0, i, labels[i], ha='center', va='center')

plt.show()

这段代码将绘制一个包含6个节点和5个流量的桑基图。具体来说，每个节点由一个圆圈表示，圆圈的大小表示节点的权重，节点的标签显示在圆圈中心。流量由箭头表示，箭头的颜色表示流入或流出的方向，箭头的宽度和长度表示流量大小，流量大小显示在箭头中心。