knitro solver

[k_7...@yahoo.com]

Hi Johan,


I'm wondering if I can use knitro solver inside optimizer command ? if yes, does it need to set some options before using it?

Thank you very much in advance

Klanter

[Johan Löfberg]

Yes, should work

sdpvar x
sdpvar u
P = optimizer(x>=u,(x+5)^2,sdpsettings('solver','knitro'),u,x)
P{.5}
Optimizer object with 1 inputs and 1 outputs.

ans =

    0.5000

[Klanter]

Thanks Johan for reply

I executed your code above and got this result:

??? Error using ==> optimizer.optimizer at 194

Failed exporting the model: Solver not found (+knitro)

 

I have trial version with license I verified it by this code:

[x fval] = knitromatlab(@(x)cos(x),1)

Final Statistics

----------------

Final objective value               = -1.00000000000000e+000

Final feasibility error (abs / rel) =   0.00e+000 / 0.00e+000

Final optimality error  (abs / rel) =   2.37e-009 / 2.37e-009

# of iterations                     =          7 

# of CG iterations                  =          0 

# of function evaluations           =         12

# of gradient evaluations           =          8

Total program time (secs)           =       0.083 (     0.063 CPU time)

Time spent in evaluations (secs)    =       0.014

===============================================================================

x =

    3.1416

fval =

   -1.0000

[Johan Löfberg]

Which version? 9.0 is required

[Johan Löfberg]

and are you really using the latest version of YALMIP?

[Klanter]

KNITRO 9.0

I downloaded it yesterday!

[Klanter]

yalmip version

ans =

20131220

[Johan Löfberg]

What is returned from

yalmip('version')

and

which -all 'knitromatlab'

[Johan Löfberg]

Are you sure you downloaded it yesterday? YALMIP was updated on the 17th (the link on the download page said otherwise, but the latest is always in the file YALMIP.zip, which downloaded correctly when I tried just now. Updated the name on the link though to the correct version number)

Anyway, you are running an old version.

[Johan Löfberg]

OK, problem solved then., Install the latest version of YALMIP which adds support to KNITRO and it will work.

[Klanter]

Thank you very much! I'm really appreciate your answer.

[ahmad hdr]

Dear Dr. Lofberg

I have the same problem. I just received the trial version of Knitro (version 13.2), running into MATALB (R2020b) with the command: 

[x fval] = knitro_nlp(@(x)sin(x),1) 

It is ok; however, when running yalmip('test'), it shows that knitro "not found." 

{yalmip('version') = 20210331}

It would be appreciated if you could guide me through this. 

[Johan Löfberg]

It is simply not supported, so you only way forward is either to add support for it in yalmip your self (contributions welcome), or wait for some release where this has been done

[Johan Löfberg]

Update for 13.1+ available in the develop branch now