GAMS — The Solver Manuals - Available Software

240 DICOPT
**** ERRORS(S) IN EQUATION loss(cc,sw)
2 instance(s) of - UNDEFINED REAL POWER (RETURNED 0.0E+00)
If such errors appear you can increase the DOMLIM limit, but often it is better to prevent the errors to occur.
In many cases this can be accomplished by adding appropriate bounds. Sometimes you will need to add
extra variables and equations to accomplish this. For instance with an expression like log(x − y), you may
want to introduce a variable z > ε and an equation z = x − y, so that the expression can be rewritten as
log(z).
option iterlim = n;
This option sets a limit on the total accumulated (minor) iterations performed in the MIP and NLP subproblems.
The default is 1000.
option minlp = dicopt;
Selects DICOPT to solve MINLP problems.
option mip = s;
This option sets the MIP solver to be used for the MIP master problems. Note that changing from one MIP
solver to another can lead to different results, and may cause DICOPT to follow a different path.
option nlp = s;
This option sets the NLP solver to be used for the NLP sub-problems. Note that changing from one NLP
solver to another can lead to different results, and may cause DICOPT to follow a different path.
option optca = x;
This option is ignored. MIP master problems are solved to optimality unless specified differently in the
DICOPT option file.
option optcr = x;
This option is ignored. MIP master problems are solved to optimality unless specified differently in the
DICOPT option file.
option reslim = x;
This option sets a limit on the total accumulated time (in seconds) spent inside DICOPT and the subsolvers.
The default is 1000 seconds.
option sysout = on;
This option will print extra information to the listing file.
In the list above (and in the following) n indicates an integer number. GAMS will also accept fractional values:
they will be rounded. Options marked with an x parameter expect a real number. Options with an s parameter,
expect a string argument.
7.2 The Model Suffix
Some options are set by assigning a value to a model suffix, as in:
model m /all/;
m.optfile=1;
solve m using minlp minimizing z;
Here follows a list of model suffices that affect the behavoir of DICOPT:
m.dictfile = 1;
This option tells GAMS to write a dictionary file containing information about GAMS identifiers (equation
and variables names). This information is needed when the DICOPT option nlptracelevel is used.
Otherwise this option can be ignored.