Cannot perform the operation: {convex} .* {log-affine}

Hello everyone,

I am a newbie and need to help on this question.

When I run this problem in CVX

function miup_iter = get_miup(tmup_iter,tup_iter,silay,usernum,W,N0,gi,Eimax,roui,Qimax,si,mi,vilocal,vs)
cvx_begin
variable d
variable miup(1,usernum)
minimize( d + tup_iter + sum(miup(1:usernum))/vs )
subject to
……
for i = 1:usernum
    if i == 2
        continue;
    end
    tmup_iter * W * N0 / gi(i) * (exp(miup(i)*(1/(tmup_iter*W)) * log(2)) - 1)  * exp(sum(miup(1:i-1)) * (1/(tmup_iter*W)) * log(2) ) + ...
        tup_iter * W * N0 / gi(i) * (exp(silay(i)*(1/(tup_iter*W)) * log(2)) - 1) * exp(sum(silay(1:i-1)) * (1/(tup_iter*W)) * log(2) )  <= Eimax(i)
end
cvx_end

I received an error about the constraint that"Cannot perform the operation: {convex} .* {log-affine}".I think the constraint is convex.

How can I solve this error?

Thank you :grinning:

I haven’t carefully checked what you have. But in this forum, it is not sufficient to think a constraint is convex, it is your responsibility to prove it.