How can i define constraint in my optimization problem?

I have a Constraint HP>0.0025 and HP is the function of PS. i dont know how to define this constraint. when i am using it directicly in inequaliity constraint i gives error that row dimension doesnot match. and as a non linear constraint i used it like this " c = HP - 0.0025". Need Help.

[Walter Roberson]

Is PS one of the parameters, and HP is computed from PS? If so then use one of the minimizers such as fmincon that support nonlinear constraint functions, and have that function compute HP based upon the input PS and have it compute 0.0025-HP

[Momin khan]

thank you for your response. i am using fmincon and PS is the optimal value, and HP is computed by using PS in the equation. and i have used this 0.0025-HP. is there any other method for constraint HP>0.0025?

[Walter Roberson]

No, not unless HP is a linear calculation.

Note that there are circumstances under which nonlinear constraints are not enforced, in particular during the initial gradient estimation.