# Vincent

• Total activity 24
• Last activity
• Member since
• Following 0 users
• Followed by 0 users
• Subscriptions 6

## Activity overview

Latest activity by Vincent
• Vincent commented,

Thank you Mario Ruthmair

• Vincent created a post,

### Runtime for multiple scenarios

Sometimes, I encounter a situation where my model's runtime decreases when the number of scenarios slightly increases. I'd appreciate any insight into the potential reasons, as this seems counterin...

• Vincent commented,

Thanks very much for your quick and detailed response.

• Vincent created a post,

### Merging a binary decision variable with a continuous variable (semi-binary/continuous)

I have two decision variables defined as x = m.addVars(((i, j) for i, j in arcs if f[i][j] == 0),vtype=GRB.BINARY, name='x')y = m.addVars(((i, j) for i, j in arcs if f[i][j] == 1),vtype=GRB.CONTINU...

• Vincent commented,

Hi Matthias, Thanks for your help. Is the itertools.product method faster than the first one? Thanks,Vincent

• Vincent created a post,

### How to use addVars() in GurobiPy using "if" conditional?

I have defined a variable using addVar() method as follows: for i in range(no_nodes): for j in range(no_nodes): for k in O: if fij[i][j]==1 or mij[i][j]==1: x[i,j,k] = m.addVar(vtyp...

• Vincent commented,

That was actually the issue! Thank you Danial Ramin.

• Vincent commented,

Hi,I am setting the LogFile parameter manually but the file is almost empty! The only part copied to my logfile is this: Gurobi 9.0.1 (win64) logging started 04/22/20 14:49:32Changed value of param...

• Vincent created a post,

### Why does MIPFocus value change the optimal solution?

Hi, - When I select MIPFocus=1, the optimal solution is equal to 1.79542 with 0.0000% gap.- When I select MIPFocus=3, the optimal solution changes to 1.75932 with 0.0000% gap. I cannot understand w...

• Vincent commented,

Thanks, Eli Towle! I've already tried that but, other than the degrade in the first and second objectives, there is another downside. When I add a constraint to the second or third objective to dis...