Plotting Multiple images with defined size

images = [img, edge_roberts, edge_prewitt, edge_sobel]
names = ["input", "roberts", "prewitt", "sobel"]

fig = plt.figure(figsize = (8, 8))

for i in range(4):
  fig.add_subplot(2, 2, i + 1)
  plt.title(names[i])
  plt.imshow(images[i], cmap = 'gray')

Simplest way to plot

plt.figure(figsize = (8, 8))

for i in range(4):
plt.subplot(2, 2, i + 1)
plt.imshow(images[i])