-------- Forwarded Message --------
Date: Tue, 17 Jan 2023 20:33:01 -0800 Subject: Integer solutions To: '[email protected]' <[email protected]> From: [email protected] > <!-- > /* Font Definitions */ > @font-face > {font-family:"Cambria Math"; > panose-1:2 4 5 3 5 4 6 3 2 4;} > @font-face > {font-family:Calibri; > panose-1:2 15 5 2 2 2 4 3 2 4;} > /* Style Definitions */ > p.MsoNormal, li.MsoNormal, div.MsoNormal > {margin:0in; > font-size:11.0pt; > font-family:"Calibri",sans-serif;} > span.EmailStyle17 > {mso-style-type:personal-compose; > font-family:"Calibri",sans-serif; > color:windowtext;} > .MsoChpDefault > {mso-style-type:export-only; > font-family:"Calibri",sans-serif;} > @page WordSection1 > {size:8.5in 11.0in; > margin:1.0in 1.0in 1.0in 1.0in;} > div.WordSection1 > {page:WordSection1;} > -->Hi, > If I call glp_simplex without specifying that any variables be > integers and then call glp_intop it looks like it at least makes the > objective function an integer. > If I specify the variable should be integers as well via > glp_set_col_kind with GLP_IV then I found the time to solve the > problem was much larger (well to be expected I guess). > What is the process I should follow if I want to perform a real > relaxation of a full integer problem and only go to integers if the > problem is not satisfiable (mostly what I use the calls for)? > I couldn’t really see this spelled out in the docs. > I use the object function to find redundant constraints and I can see > this with both real and integer objectives. Obviously doing the real > case first would be faster. Likewise I determine feasibility of a > system of inequalities with a zero objective and want to do this in > both reals and then integers. > Thanks. > Neill. >
