Writing data out to text files

You can write out values in an analogous way to reading them in

initializations to 'cost.dat'
  COST
end-initializations

To write out the solution values of variables, or other solution values (slack, activity, dual, reduced cost) you must first put the values into a data table

declarations
  make_sol: array(ITEMS,TIME) of real
  obj_sol: real
end-declarations

forall(i in ITEMS, t in TIME)
  make_sol(i,t) := getsol(make(i,t))

obj_sol := getobjval

initializations to 'make.dat'
  make_sol
  obj_sol
end-initializations

Alternatively, you can use evaluation of directly in the initializations block

initializations to 'make.dat'
  evaluation of
    array(i in ITEMS, t in TIME) getsol(make(i,t)) as 'make_sol'
  evaluation of getobjval as 'obj_sol'
end-initializations