Multiple lines on a plot using Matplotlib

July 13, 2022

I am generating 4 rectangles using ax.add_patch. I want to connect these rectangles using single lines as shown in the expected output.

import matplotlib as mpl
import matplotlib.pyplot as plt
from matplotlib.patches import Rectangle

fig,ax = plt.subplots(1)
n=2
for i in range(0,n):
    for j in range(0,n):
        rect = mpl.patches.Rectangle((200+200*i,200+200*j),10*n, 10*n, linewidth=1, edgecolor='black', facecolor='black')
        ax.add_patch(rect)

ax.set_xlim(left = 0, right = 220*n)
ax.set_ylim(bottom = 0, top = 220*n)
plt.show()

The current output is

The expected output is

>Solution :

Try placing vertical and horizontal lines at those positions

import matplotlib as mpl
import matplotlib.pyplot as plt
from matplotlib.patches import Rectangle

fig,ax = plt.subplots(1)
n=2
for i in range(0,n):
    for j in range(0,n):
        rect = mpl.patches.Rectangle((200+200*i,200+200*j),10*n, 10*n, linewidth=1, edgecolor='black', facecolor='black')
        ax.add_patch(rect)
    ax.hlines(200+200*i+10, 200, 400, zorder=0)
    ax.vlines(200+200*i+10, 200, 400, zorder=0)

ax.set_xlim(left = 0, right = 220*n)
ax.set_ylim(bottom = 0, top = 220*n)
plt.show()