MATPOWER/matpower

after installing gurobi, how to let matpower know it?

yanda1234 opened this issue · 18 comments

yanda1234 commented

Hi Dr. Zimmerman,

Sorry to disturb you before holiday. For some reason, I need to install gurobi again, but after that, I found matpower cannot recognize it.
I believe gurobi is installed and the link between matlab and gurobi is also installed, since I tested a gurobi case from matlab.
However, the problem is matpower cannot call gurobi. I tried mpoption('gurobi.method',1) and mpver. And the first command brought back me an error message, while the second one got me gurobi is not installed. Do you know how to fix it? Kindly advise.

Many thanks.

Best,
Yanda

rdzman commented

MATPOWER checks once for the presence of external solvers, then caches the result to make future checks faster. You can clear that cache by doing ...

have_feature('all', 'clear_cache')

... or simply restart your MATLAB session. Then it should find it.

yanda1234 commented

Hi Dr. Zimmerman,

This function doesn't work for me.
image
image
image

And I restarted matlab, but matpower still cannot recognize gurobi. Do you have any thoughts?

Best,
Yanda

rdzman commented

What version of MATPOWER are you using?
And what is the output when you type: which gurobi ?

yanda1234 commented

image
Matpower version is 7.0

rdzman commented

The fact that it can't find have_feature() means that either you are using a version of MATPOWER before 7.1, or it is not properly installed.

But if Gurobi is in the MATLAB path after restart, it should find it anyway.

yanda1234 commented
rdzman commented

Hmm, I'm not aware of any issues with MATPOWER 7.0 and Gurobi 9.5.2.
What does exist('gurobi', 'file') return?
And what happens if you try the following?

model = struct( ...
    'A', sparse(1), ...
    'rhs', 1, ...
    'sense', '=', ...
    'vtype', 'C', ...
    'obj', 1, ...
    'modelsense', 'min' ...
);
params = struct( ...
    'outputflag', 0 ...
);
result = gurobi(model, params);
rdzman commented

Yes, Gurobi must be in the MATLAB path for MATPOWER to find it ... regardless of the version of MATPOWER.

yanda1234 commented

If I add path each time, instead of saving there permanently, is it ok?

rdzman commented

As long as you add it to your path before MATPOWER tries to check for its availability you should be fine. If MATPOWER checks first, then it will not find it and will cache that result and not check again.

yanda1234 commented

I see. Is there any problem for the model, params and result?

rdzman commented

No, I was just hoping it would produce an error that would help me figure out the problem. But you must have had Gurobi in your path that time, so no error.

rdzman commented

But it's not a bad idea to update to the latest MATPOWER.

yanda1234 commented
yanda1234 commented

Hi Dr. Zimmerman,

After I cleared cache, the mpver works, which means matpower can recognize gurobi, right?
image
However, mpoption still doesn't work. Do you have any thoughts?
image

Best,
Yanda

rdzman commented

I don't understand how that can happen. Can you start a new MATLAB session, make sure Gurobi is in the path before using any MATPOWER commands, then try mpver and mpoption('gurobi.method', 1)?

Both should work. If not, maybe something got corrupted with your MATPOWER install and you need to reinstall (or better yet, upgrade) MATPOWER.

yanda1234 commented

It is interesting. It works this time, although I still don't know why... Thanks a lot.