How to express (x-y)?

How to express the constrain in CVX?
the dimension of tao(k,n) and pk(k,n) are both K*N.
0<tao(k,n)<1 and 0<pk(k,n)<1


I’m not sure where the difficulty is. Maybe just write them down as what they are. or, write
sum((tao-pk).*(taor-pkr),2) <=T*xxxx;

Thank you for your reply! There is no difficulty.I wrote them down as what they were,then I get an error as follows.

my code:

for k=1:K   
    for n=1:N


   Disciplined convex programming error:
      Cannot perform the operation: {real affine} .* {invalid}

The {invalid} comes from your last iteration (it might have been Failed,Infeasible,etc.), which we don’t know anything about. So it is not about how to express (x-y), but how to debug Failed, Infeasible,etc.

Ok, thank you very much!

Further expanding on @jackfsuia 's point, the input data contains NaN, which CVX considers to be invalid.