Re: Problem minimizing with sqp

[Brett Green]

How embarrassing... I had put a parabola there earlier, changed it to experiment, left for a meeting, and had forgotten about the change by the time I returned.

Thank you both for pointing that out! I'm relieved that it was something so simple.

- Brett Green

On Fri, Jul 12, 2019 at 5:26 PM Doug Stewart <address@hidden> wrote:

On Fri, Jul 12, 2019 at 3:52 PM Brett Green <address@hidden> wrote:

I need to minimize a function of two variables. It looks like sqp is the sort of function I should use for that.

As a test to make sure I was using the function properly, I put in the following paraboloid:

f = @(v) 2*v(1).^3 + 3*v(2).^4;

[x, obj, info, iter, nf, lambda] = sqp([1,3],f)

was given the result

x =
  -1.1753e+11
   1.7162e+08

Clearly this is completely wrong - the minimum of the function f is at (0,0)! Have I done something wrong here or is it a bug?

- Brett Green

if you try

f = @(v) abs(2*(v(1)-1).^3) + 3*v(2).^4;
[x, obj, info, iter, nf, lambda] = sqp([1,3],f)

it finds a minimum!!! at +1

--

DAS