"Not-a-Number" NaN with arithmetical operations

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Hello,

I have a doubt. I am doing a division between two vectors (65356x1 size). Both vectors include 0s and It divides each array element. The problem is when it divides by 0s, operation (0/0), its result is not NaN, is 0!. I think It is wrong... Are there some way to get the correct result (with NaNs)?

The code is very simple: Mat G = im_g/tableReshaped; (where img_g and tableReshaped are 65356x1 matrices).