Here is one part of my codes.

```
variable q(N,2,J) ;
...
minimize(P);
subject to
for n=1:N
for k=1:K
for j=1:J
RR51(k,j,n)=B(k,j,n)*log2(1+EgG2A*a0*P*inv_pos(pow_pos(norm(q(n,:,j)-qM(k,:)),2)+H^2)/o2^2);
end
end
end
```

Disciplined convex programming error:

Illegal operation: pow_p( {convex}, {-1} )

出错 cvx/inv_pos (line 5)

y = pow_cvx( x, -1, ‘pow_p’ );

However, there is an error in the above lines. Why is it wrong? What should I change?