20091104
gurobi.c, README.gurobi: fix a glitch with iisfind=1 on infeasible
problems: solve_result_num previously indicated a failure rather
than infeasible.
20091214
gurobi.c: add "cutoff" keyword to possibilities for $gurobi_options.
makefile.u: add rule for xsum.out.
README.gurobi: add brief MacOSX discussion.
20100309
gurobi.c: fix bugs in handling .ref and .sosno suffixes.
20100418
gurobi.c: extend for Gubobi 3.0; should continue to work with older
versions of Gurobi as well. New facilities include keywords for
requesting .sol files of alternative MIP solutions; new synonym
lpmethod for simplex and a way to select the (new) barrier algorithm
(lpmethod=2); new tolerances and an iteration limit for the barrier
method; control of crossover from barrier solution to basic solution;
"mipfocus" to help direct the MIP solver; "predual" to present the
dual of an LP to the solver; "pumppasses" to control the feasibility
pump; and "symmetry" to control the MIP solver's detection of
symmetry. See the output of "gurobi -=" for a summary of the
currently available keywords. Complete list of new keywords for
Gurobi 3.0: aggfill, ams_eps, ams_epsabs, ams_limit, ams_stub,
barconvtol, barcorrectors, bariterlim, barorder, crossover,
crossoverbasis, lpmethod, mipfocus, mipgapabs, networkcuts, param,
paramfile, predeprow, predual, prepases, pumppasses, resultfile,
rins, submipcuts, symmetry.
20100424
gurobi.c: fix a couple of typos in the "-=" output; correct
spelling of "prepasses" and for now make "prepases" a deprecated
synonym for "prepasses".
20100512
gurobi.c: adjust for a gratuitous parameter name change
("LogfileName" to "LogFile") between versions 2 and 3.
20100523
gurobi.c: adding keyword return_mipgap for returning suffixes
absmipgap and relmipgap on objectives and problems. (These values
could already be computed from the bestbound suffix.)
20100720
gurobi.c: distinguish explicitly zero initial guesses from those
that are zero by default. This affects MIP starting guesses.
20100928
gurobi.c: expand description of sos2 (shown with "gurobi -=").
20101021
gurobi.c: fix some bugs in statmsg() with error messages not
normally seen.
20101105
gurobi.c, README.gurobi: update for Gurobi 4.0.
20101115
gurobi.c: fix a bug (introduced in adjustments for Gurobi 4) that
sometimes caused the constant term in objectives to be treated as 0.
This affected the objective value reported.
20101207
gurobi.c, README.gurobi: set solve_result_num = 567 if the problem has
complementarity constraints.
20110322
gurobi.c: fix a bug in handling problems with integer variables
(including binary variables) and piecewise-linear terms: the wrong
variables were likely treated as integer. Fix a bug with "writeprob"
that could occur in problems with piecewise-linear terms: a call on
GRBupdatemodel() was missing, which could affect, e.g., a *.lp file
specified by writeprob.
20110426
gurobi.c, README.gurobi: update to Gurobi 4.5. The updated gurobi.c
should still work with earlier versions. The new .unbdd and .dunbdd
suffixes (for primal and dual rays of unboundedness) are not yet
reliable.
20110728
gurobi.c: fix a glitch with sos=1 in $gurobi_options that prevented
.sosno and .ref from being used in problems with only continuous
variables.
20110920
gurobi.c: add "method"; move the "lpmethod" description to "method"
and list lpmethod as a synonym for method. (Driver date 20110907.)
README.gurobi, makefile.*: minor tweaks for less dependence on the
particular version of Gurobi.
20111109
gurobi.c: fix a minor glitch in reporting the names of alternate
solution files generated when ams_stub is specified in $gurobi_options.
Update for use with Gurobi 4.6; new keywords:
presparsify
priorities
sifting
siftmethod
zeroobjnodes
The priorities keyword controls whether variable.priority values, if
available, are passed to Gurobi. (Default = yes.)
20120504
gurobi.c, README.gurobi, makefile.u: update for Gurobi 5.0. The
updated gurobi.c should still work with earlier versions of Gurobi.
20120511
gurobi.c: fix a bug (fault) in supplying a warm start.
20120524
gurobi.c: fix a typo in the "gurobi -=" output.
20120606
gurobi.c: fix a glitch in providing a dual initial guess (when
available from a previous solve) in problems with quadratic constraints,
leading to the message "Index out of range for attribute 'DStart'."
20120828
gurobi.c: on MIP problems, when basis >= 2 and method >= 2, change
method to 1 before trying to get the requested output basis. Also
adjust the description of "method" and remove "rootmethod", which
went away in Gurobi 4.0.
20120927
gurobi.c: adjust to return dual variables on quadratically constrained
problems with integer variables when qcpdual=1 is specified.
Also, for debugging, add ".fix_lp" and ".fix_mps" to the suffixes
accepted by the "writeprob" keyword.
20121006
Add keyword "version", to report version details before solving
the problem.
20121101
Fix a bug with problems involving both nonconvex piecewise-linear
terms and range constraints. The adjustments for ranges were wrong,
resulting in the error message "Index is out of range" or other trouble.
20121116
Minor tweaks to two error messages and other minor cleanups.
20130109
Update for Gurobi 5.1: add keywords impstartnodes and seed.
20130204
Fix an off-by-one error in the description of sos2 in the -= output.
20130206
Fix a possible fault, introduced 20120504 (for Gurobi versions >= 5),
with problems having a dual initial guess but no incoming basis.
20130328
Update for Gurobi 5.5: add keywords
concurrentmip
feasrelaxbigm
impstartnodes
numericfocus
seed
server
server_password
server_port
server_priority
server_timeout
serverlic
tunebase
tuneoutput
tuneresults
tunetimelimit
tunetrials
20130419
Correct the descriptions of "aggfill" (default value) and "cutoff" in
the "-=" output. When the objective is no better than cutoff, report
"objective cutoff" rather than "cutoff reached".
20131003
Updates for Gurobi 5.6. New keywords
disconnected
pool_mip
pool_password
pool_servers
pool_tunejobs
presos1bigm
presos2bigm
See the output of "gurobi -=" for details.
20131101
Add keyword "objrep" with description
objrep Whether to replace
minimize obj: v;
with
minimize obj: f(x)
when variable v appears linearly in exactly one
constraint of the form
s.t. c: v >= f(x);
or
s.t. c: v == f(x);
Possible objrep values:
0 = no
1 = yes for v >= f(x)
2 = yes for v == f(x) (default)
3 = yes in both cases
For maximization problems, ">= f(x)" is changed to
"<= f(x)" in the description above.
20131113
Fix a typo in the "gurobi -=" output: change "tuneparbase" to "tunebase"
(twice, in the description of "tunebase").
20131114
Fix a glitch, probably introduced in version 20131003, that kept "cuts"
from being recognized in $gurobi_options.