GAMS — The Solver Manuals - Available Software

346 MINOS
B. A. Murtagh, University of New South Wales
P. E. Gill, University of California at San Diego,
W. Murray, M. A. Saunders, and M. H. Wright,
Systems Optimization Laboratory, Stanford University
Work space allocated -- 2.21 Mb
Reading Rows...
Reading Columns...
Itn ninf sinf objective
100 6 1.454E+00 -2.05756624E+04
200 0 0.000E+00 2.08164754E+04
300 0 0.000E+00 1.62252805E+04
400 0 0.000E+00 1.42039308E+04
500 0 0.000E+00 1.34920341E+04
600 0 0.000E+00 1.27183672E+04
EXIT - Optimal Solution found, objective: 12657.77
--- Restarting execution
--- TURKPOW.GMS(205) 0 Mb
--- Reading solution for model turkey
--- TURKPOW.GMS(230) 2 Mb
*** Status: Normal completion
The first line that is written by MINOS is the version string: MINOS-Link May 25, 2002 WIN.M5.M5 20.6
023.046.040.VIS GAMS/MINOS 5.5. This line identifies which version of the MINOS libraries and links you are
using, and is only to be deciphered by GAMS support personnel.
After some advertisement text we see the amount of work space that is allocated: 2.08 Mb. When MINOS is
loaded, the amount of memory needed is first estimated. This estimate is based on statistics like the number
of rows, columns and non-zeros. This amount of memory is then allocated and the problem is then loaded into
MINOS.
The columns have the following meaning:
Itn Iteration number.
ninf Number of infeasibilities. If nonzero the model is still infeasible.
sinf The sum of the infeasibilities. This number is minimized during Phase I. Once the model is feasible this
number is zero.
objective The value of the objective function: z = ∑ c i x i . In phase II this number is maximized or minimized.
In phase I it may move in the wrong direction.
The final line indicates the exit status of MINOS.
8.2 Linearly Constrained NLP’s
The log is basically the same as for linear models. The only difference is that not only matrix row and columns
need to be loaded, but also instructions for evaluating functions and gradients.
The log for the problem WEAPONS is as follows:
GAMS Rev 132 Copyright (C) 1987-2002 GAMS Development. All rights reserved
Licensee: Erwin Kalvelagen
G020307:1807CP-WIN