For those who want to display images side by side as soon as possible with Python's matplotlib

Source code

import matplotlib.pyplot as plt
import cv2
import os

root = "./data" #The folder that contains the images. Please change accordingly
lsdir = os.listdir(root)

imgs = []
for l in lsdir:
    target = os.path.join(root,l)
    img = cv2.imread(target)
    img = cv2.cvtColor(img,cv2.COLOR_BGR2RGB) #Color conversion for display in pyplot
    imgs.append(img)

shownumber = 10 #Number of images to arrange
showaxis = 1

while(showaxis*showaxis < shownumber):
    showaxis += 1

cnt = 0
while(1):
    #limit = 30
    #if cnt >= limit:
    #    break
    fig,axs = plt.subplots(showaxis,showaxis)
    ar = axs.ravel()
    for i in range(showaxis*showaxis):
        ar[i].axis('off')
        if i < shownumber:
            ar[i].imshow(imgs[cnt])
            cnt += 1
    plt.show()

Display result

shownumber = 9

shownumber = 10

Why i wrote this article

――I feel like I'm wondering about matplotlib every time I display an image, so I wanted to set a standard for myself. --Since specifying row and column is subtly annoying, I wanted the code to work just by specifying the number of displays. ――I wanted to create a page where such source code would hit immediately

Code description

--Specify a folder and read it with cv2.imread, and make it an array called ʻimgs. --OpenCV is read in BGR format, so convert it to RGB format with cv2.cvtColor --If you specify the display numbershow number, find the minimum square that satisfies it, and set one side as show axis`.

while(showaxis*showaxis < shownumber):
    showaxis += 1

--Prepare a graph with plt.subplots with as many rows and columns as show axis. ――Since it is troublesome to specify the vertical position and horizontal position of ʻaxs, make a series of arrays with ʻaxs.ravel (). --Display images with ʻimshow and ʻaxis ('off') as many as show number per loop --Keep spinning the loop until ʻimgs` runs out

Note that due to the structure of the code, an out-of-range reference error will definitely occur in the end. I wrote the escape process in the comments.