Hi all,

I got one issue reporting “System Failure”. My opt. problem has a mixed-integer quadratic objective function with linear constraints, and I defined it as an MIQCP problem. the report summary is as follows.

```
S O L V E S U M M A R Y
MODEL dualspregu OBJECTIVE subdualregu
TYPE MIQCP DIRECTION MINIMIZE
SOLVER CPLEX FROM LINE 666
**** SOLVER STATUS 13 System Failure
**** MODEL STATUS 13 Error No Solution
**** OBJECTIVE VALUE NA
RESOURCE USAGE, LIMIT NA 100000000000000.000
ITERATION COUNT, LIMIT NA 2000000000
EVALUATION ERRORS NA 0
General nonlinearity detected in row subobjregu
*** Could not load data from file: Detected 1 general nonlinear rows in model
No solution returned
```

Actually I am aware that MIQCP is mixed-integer quadratically constrained programming, and my model is mixed-integer quadratic objective function with linear constraints, which should be termed as MIQP problem, according to IBM CPLEX website. But when I go through the GAMS CPLEX API documentation:

https://www.gams.com/latest/docs/S_CPLEX.html

I found one sentence:

"QP models are a special case that can be reformulated to have a quadratic objective function and only linear constraints. Those are automatically reformulated from GAMS QCP models. "

Then I am quite confused why it didn’t work. I also tried to term my problem as MIQP but it is not a solve keyword provided by GAMS.

Does anyone have idea for how to define a mixed-integer quadratic programming with linear constraints in GAMS? Thanks in advance.

Best,

Gabriel