CVX programming error: Cannot perform the operation: {convex} ./ {convex}

Uncategorized
Dec 27, 2023
J


The picture is one of the constraints in my convex optimization (cvx) problem. ‘t’ and ‘Q’ are the optimization variable. However, when I run the code, the following error message appears: ‘Cannot perform the operation: {convex} ./ {convex}.’ I know the issue lies on the left side of the constraint, but I haven’t come up with a proper way to reformulate this inequality. Please provide your suggestions if possible.

M

Please show us your proof the optimization problem is convex. You haven’t shown the whole problem, so readers can’t know. However, what you do show is a linear fractional form. Is the denominator always positive?

Perhaps this can be handled by techniques along the lines of section 4.3.2 “Linear-fractional programming” of Convex Optimization – Boyd and Vandenberghe, or the problem is quasi-convex and can be handled by the bisection algorithm in section 4.2.5 “Quasiconvex optimization” of that book.

However, perhaps you are not telling us everything? If Q and t were the only optimization variables, and everything else was input data, I believe you would have gotten the error message, {affine}/{affine}, not {convex}/{convex}. So that may put my teh applicability of my preceding paragraph into greater doubt.

J
Replying to #2

I check the cvx problem and code again. The error message should be{affine}/{affine} as you said. And the denominator is always positive. Q and t are the only optimization variables. I will continue to try to solve the problem. Truly grateful for your help. And please tell me if you have any other suggestions.