Frequently asked question (and more)

Q: I've been using a previous version of YALMIP, but after installing the new version nothing works.
A: Restart Matlab.

Q: ...still doesn't work!
A: Added all the paths? (/yalmip, /yalmip/extras, /yalmip/sos, /yalmip/demos, /yalmip/solvers)

Q: My version of SDPT3-3.02 does not work with YALMIP
A: Download SDPT3-3.02 and compile (code updated without version increment)

Q: SDPT3 (or SeDuMi) does not work.
A: Make sure not to have both SDPT3 and SeDuMi on the Matlab path

Q: CSDP does not work.
A: Do you have CSDP in your system path?

Q: It is soo slow!
A: Running on LINUX with YALMIP chucked away somewhere on a network? Yep, I know...

Q: I already have LMILAB and LINPROG installed, do I need any other solver?
A: Yes, at-least if you intend to solve anything but a few small problems.

Q: There are soo many solvers, which one should I use?
A: SeDuMi is a good general purpose SDP solver, with binaries available for most platforms. (not necessarily the best solver though)

Q: Are inequalities really strict?
A: There is no distinction in YALMIP between strict or non-strict inequalities. How the inequality is treated (strict or non-strict) depends on the solver.

Q: I can't write X(end) when X is an sdpvar-matrix
A: Use 2 arguments, for example X(1,end) or X(end,1).

Q: Why can't I write X = eye(2); X(1,1)=sdpvar(1,1)?
A: Work in progress, seems to be a bug in Matlab.

Q: I have found a bug, what to do?
A: Send a mail to loefberg@control.ee.ethz.ch. Type ver in Matlab and include the result in the mail. If possible, include the code (as simple as possible) that generated the fault, otherwise, include at-least the error message etc. The more information the better.

Q: I have an idea for a new feature, what to do?
A: Send a mail to loefberg@control.ee.ethz.ch. However, I only add new features when I need them my self, but if your idea is good enough, I might realize that I need it.

Q: What does YALMIP mean?
A: Used to be short for Yet Another LMI Parser. However, since YALMIP is much more than a LMI parser now, it dies not mean anything more. Perhaps Yet Another Lame Modeling Initiative.

Q: Defining bilinear matrix inequalities using the command lmi and solving LPs with a command called solvesdp, kind'a weird if you ask me!
A: Yes...These names are kept or backwards compability. Hence the command lmi does not mean Linear Matrix Inequalitiy, but List of Matrix Inequalities and solvesdp is short for solve symbolic decision problem. Or what ever you want them to mean.