why is this error coming?
If we can plot (120,140,3) shape image then why
not (28,28,1)shape image.
After reshaping image is correctly shown how?
CNN 08 - Building Fashion MNIST CNN in Keras
You cannot plot 28,28,1 using matplotlib’s imshow. This is because if your pass 3 dimension numpy array than matplotlib’s imshow function expects 3rd value in numpy’array’s shape to be 3, corresponding to 3 channels, RGB and not 1. But on other hand if you pass 2D numpy array than it can be plotted easily, means matlplotlib’s imshow function understands that it is recieving a gray scale image. It than assigns color map accordingly and you see a colored image which is actully grayscale.
You can plot original gray scale image by using cmap = ‘gray’ in imshow function.
Hope this helped you 
got it…
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