Re: [Bug-glpk] Problem in the MIP problem

[Andrew Makhorin]

>> I check my code and I resolve my problem. But, an other problem appear.
>> 
>> When I fix a variable at one, and after, I define the type as binary, then
>> the lower bound is 0 instead of 1.
>> 
>> I resolve this problem in declaring variables as integer. But, why
>> glp_set_col_kind redefine the lower bound

Because binarity assumes that.

The glpk reference manual, section "Mixed integer programming routines",
subsection "Set (change) column kind" says:

   "Setting a column kind to GLP_BV has the same effect as if it were
   set to GLP_IV, its lower bound were set 0, and its upper bound were
   set to 1."