Rescaling a variable with NaNs

I want to rescale my matrix(56,53), it is filled with numbers from 1 to 7 and NaNs. I would like to change the 1 to 7, 2 to 6, 3 to 5 and 5 to 3, 6 to 2, and 7 to 1.

I found this solution https://stackoverflow.com/questions/48542055/reverse-coding-in-matlab but it does not work for me even though I replaced the NaNs with 0.

Any suggestions? Thank you in advance.

Answer 1

[Stephen23]

>> M = randi(7,3,5);
>> M(randi(numel(M),1,3)) = NaN
M =
     6     7     7     6     4
     3   NaN     5   NaN     6
     5     4   NaN     2     7
>> Z = 8-M
Z =
     2     1     1     2     4
     5   NaN     3   NaN     2
     3     4   NaN     6     1