【交点】直线与多边形相交显示

every blog every motto: You can do more than you think.
https://blog.csdn.net/weixin_39190382?type=blog

0. 前言

python 求直线与多边形交点并显示

1. 正文

1.1 步骤

import matplotlib.pyplot as plt
from shapely.geometry import LineString, Polygon

导入所需的模块和函数：

import matplotlib.pyplot as plt
from shapely.geometry import LineString, Polygon

创建直线对象和多边形对象：

line = LineString([(x1, y1), (x2, y2)])
polygon = Polygon([(x3, y3), (x4, y4), ..., (xn, yn)])

提取多边形的边界作为LineString对象：

boundary = polygon.boundary

计算直线与多边形边界的交点：

intersection = line.intersection(boundary)

将交点转换为MultiPoint对象（如果有多个交点）或Point对象（如果只有一个交点）：

if intersection.geom_type == 'MultiPoint':
    intersection_points = list(intersection)
else:
    intersection_points = [intersection]

绘制多边形、直线和交点

fig, ax = plt.subplots()
ax.plot(*boundary.xy, label='Polygon')
ax.plot(*line.xy, label='Line')

for point in intersection_points:
    ax.plot(*point.xy, 'ro', label='Intersection')

ax.legend()
plt.show()

1.2 完整代码

import matplotlib.pyplot as plt
from shapely.geometry import LineString, Polygon

# 创建直线对象和多边形对象
line = LineString([(0, 0), (3, 5)])
polygon = Polygon([(1, 1), (1, 4), (4, 4), (4, 1)])

# 提取直线的起点和终点坐标以及多边形的边界坐标
line_coords = line.xy
boundary_coords = polygon.boundary.xy

# 计算直线与多边形边界的交点
boundary = polygon.boundary
intersection = line.intersection(boundary)

if intersection.geom_type == 'MultiPoint':
    intersection_points = list(intersection)
else:
    intersection_points = [intersection]

fig, ax = plt.subplots()
ax.plot(*boundary.xy, label='Polygon')
ax.plot(*line.xy, label='Line')

for point in intersection_points:
    ax.plot(*point.xy, 'ro', label='Intersection')

ax.legend()
plt.show()