Quadratic Programming: Using Imin & Imax

[Keith_W]

Quick question about LabVIEW's Quadratic Programming VI (since the help for this particular VI is woefully unhelpful).  If I use the inequality constraint cluster, am I obligated to use both Imin and Imax?  

Right now I'm getting the {-20068: qpopt - equality constr main loop} error, but the equality constraint input is not connected to anything.  I am using the inequality constraint input, with D having size [m x n], Imin having size [0] and Imax having size [m].  Is having Imin and Imax sizes unequal a problem?  If so, what if I only have bounds in one direction?  The way that I've usually seen the inequality constraints formatted (and what Matlab's quadprog uses) is:

Ax <= b

where as LabVIEW formats the inequality constraints as:

Imin < Dx < Imax

How can the two be reconciled?

[Esteban_B]

Hi Keith,

If you don’t set up the constraints, they will have the default value of 0. I believe that you’ll need bounds in both directions, if not, one or the other could be set to 0, It’s important that the condition Imin < Dx < Imax is met.

Are you selecting also the correct instance of the VI? (IP or AS)

Regards,

[Markanbl]

Hello, 

I have the same problem but I don't understand how to solve it. I have inequality conditions A and b but no Imin, D and Imax. I suppose A corresponds to D and Imax corresponds to b, but to what does Imin correspond? How can I plug in the condition Ax<=b into Labview quadprog?

Thanks!