Shapely package - returning values of multiple intersections

Question

courtesy of the following answer, I am trying to extend this script to work for multiple curves...

Intersection of two graphs in Python, find the x value

It only plots intersections on the last straigh line. Not sure how to get it for all straight lines.

import numpy as np
import matplotlib.pyplot as plt
from shapely.geometry import LineString

x = np.arange(0, 1000)
f1 = np.arange(0, 500, .5)
f2 = np.arange(0, 1000)
f3 = np.arange(0, 2000, 2)
f4 = np.arange(0, 2000, 2)
f =np.stack((f1, f2, f3, f4))

g1 = np.sin(np.arange(0, 10, 0.01) * 2) * 500
g2 = np.sin(np.arange(0, 10, 0.01) * 2) * 600
g3 = np.sin(np.arange(0, 10, 0.01) * 2) * 800
g4 = np.sin(np.arange(0, 10, 0.01) * 2) * 1000
g =np.stack((g1, g2, g3, g4))
for i in range(len(f)):
    plt.plot(x, f[i])
for i in range(len(g)):
    plt.plot(x, g[i])

a = []
for i in range(len(g)):
    a.append(LineString(np.column_stack((x, g[i]))))
b = []
for i in range(len(f)):
    b.append(LineString(np.column_stack((x, f[i]))))
    
inter = []
for i in range(len(a)):
     inter.append(a[i].intersection(b[i]))

for i in range(len(inter)):
    if inter[i].geom_type == 'MultiPoint':
        plt.plot(*LineString(inter[i]).xy, 'o')
    elif inter[i].geom_type == 'Point':
        plt.plot(*inter[i].xy, 'o')

Answer 1

Solution:

import numpy as np
import matplotlib.pyplot as plt
from shapely.geometry import LineString

x = np.arange(0, 1000)
f1 = np.arange(0, 500, .5)
f2 = np.arange(0, 1000)
f3 = np.arange(0, 2000, 2)
f4 = np.arange(0, 2000, 2)
f =np.stack((f1, f2, f3, f4))

g1 = np.sin(np.arange(0, 10, 0.01) * 2) * 500
g2 = np.sin(np.arange(0, 10, 0.01) * 2) * 600
g3 = np.sin(np.arange(0, 10, 0.01) * 2) * 800
g4 = np.sin(np.arange(0, 10, 0.01) * 2) * 1000
g =np.stack((g1, g2, g3, g4))
for i in range(len(f)):
    plt.plot(x, f[i])
for i in range(len(g)):
    plt.plot(x, g[i])

a = []
for i in range(len(g)):
    a.append(LineString(np.column_stack((x, g[i]))))
b = []
for i in range(len(f)):
    b.append(LineString(np.column_stack((x, f[i]))))
    
inter = []
for i in range(len(a)):
    for j in range(len(b)):
     inter.append(a[i].intersection(b[j]))

for i in range(len(inter)):
    if inter[i].geom_type == 'MultiPoint':
        plt.plot(*LineString(inter[i]).xy, 'o')
    elif inter[i].geom_type == 'Point':
        plt.plot(*inter[i].xy, 'o')