How to get an optimal solution using JuMP in julia?

Question

I am using the JuMP package in julia with gurobi, and I can't seem to find any information online about how to print out an optimal solution. I can get the optimal objective value, but can't seem to find info on how to get an optimal solution. I tried solution_summary, but that gave me an error

Here's the documentation https://jump.dev/JuMP.jl/stable/tutorials/getting_started/getting_started_with_JuMP/ — Oscar Dowson, Mar 06 '22 at 06:10

score 2 · Answer 1 · answered Mar 06 '22 at 01:02

Just use value(varname) such as:

m = Model(Gurobi.Optimizer);
@variable(m, x[1:2] >= 0)
@constraint(m, [1 2;3 4] * x .<= [10,20])
@objective(m, Max, [1,2]' * x )
optimize!(m)

and now:

julia> value.(x)
2-element Vector{Float64}:
 0.0
 5.0

Note that even if the model is MILP, the value will be always Float64 so usually you end up wanting to round it in some way or other.

How to get an optimal solution using JuMP in julia?

1 Answers1