Plot multiple images with matplotlib in a single figure. Titles can be given optionally as second argument.

disp_multiple_images.py

import matplotlib.pyplot as plt
import numpy as np

def show_images(images, cols = 1, titles = None):
    """Display a list of images in a single figure with matplotlib.
    
    Parameters
    ---------
    images: List of np.arrays compatible with plt.imshow.
    
    cols (Default = 1): Number of columns in figure (number of rows is 
                        set to np.ceil(n_images/float(cols))).
    
    titles: List of titles corresponding to each image. Must have
            the same length as titles.
    """
    assert((titles is None)or (len(images) == len(titles)))
    n_images = len(images)
    if titles is None: titles = ['Image (%d)' % i for i in range(1,n_images + 1)]
    fig = plt.figure()
    for n, (image, title) in enumerate(zip(images, titles)):
        a = fig.add_subplot(cols, np.ceil(n_images/float(cols)), n + 1)
        if image.ndim == 2:
            plt.gray()
        plt.imshow(image)
        a.set_title(title)
    fig.set_size_inches(np.array(fig.get_size_inches()) * n_images)
    plt.show()

worked like a charm. Added an additional parameter to control the scaling.
line 27 : instead of n_images , i used n_images/scale. scale of 4 works fine. users can tweak

@soply Thanks!
@shang-vikas scaling is good! Thanks!

assert((titles is None)or (len(images) == len(titles)))

AssertionError

smart tool

Cool!

Thanks a lot

Great utility. Thanks man!

Good stuff, thanks!

Good job, but please note that columns and rows are swapped in add_subplot.
The correct usage should be:
a = fig.add_subplot(np.ceil(n_images/float(cols)), cols, n + 1)

Thanks sir !!

Good job, thanks

Thanks.

Thanks for sharing, good stuff!

@soply Thank you dude

this code doesn't give any error but also it doesn't show any output. so what i do?

when i run this code nothing to show any output

Thanks a lot!

Thanks, this really helped a lot!

Was trying to figure out how to do this elegantly in a function. Thanks a lot for posting this!

Thanks a lot!

Thanks!

Was looking to implement this myself, you saved me a lot of minutes. Thank you very much!

Thanks! matplotlib should implement this :)

Great!

Great work!!

Thank you so much!

It was useful, thank you!

If you're getting the following error like me:

ValueError: Number of rows must be a positive integer

You can fix it by casting the row number to int:

a = fig.add_subplot(int(np.ceil(n_images / float(cols))), cols, n + 1)

Also swapped the args order, number of rows should come first.

How to save the multiple-image figure as a new image?