Thank you,

with what you shared I have been able to create and read a basis from disk. However, I have been unable to properly load it as (it seems) the basis is stored without providing a name so it is unable to locate in the model the columns stored, see:

```
?131 Warning: No column: C1
?131 Warning: No column: C2
?131 Warning: No column: C3
```

How should I overcome this limitation?

Thank you

D

using JuMP

using Xpress

function create_optimization_problem()

model = direct_model(Xpress.Optimizer());

@variable(model, x >= 0, Int)

@variable(model, y >= 0, Int)

@variable(model, FO >= 0)

@constraint(model, c1, 10*x + 20*y <= 220 )

@constraint(model, c2, 11*x + 19*y <= 220 )

@constraint(model, c3, 12*x + 18*y <= 220 )

@constraint(model, c4, 13*x + 17*y <= 220 )

@constraint(model, c5, 14*x + 16*y <= 220 )

@constraint(model, c6, 15*x + 15*y <= 220 )

@constraint(model, c7, 16*x + 14*y <= 220 )

@constraint(model, c8, 17*x + 13*y <= 220 )

@constraint(model, c9, 18*x + 12*y <= 220 )

@constraint(model, c10, 19*x + 11*y <= 220 )

@constraint(model, c11, 20*x + 10*y <= 220 )

@constraint(model, c12, FO == x + y )

@objective(model, Max, FO)

return model

end

model = create_optimization_problem()

@time optimize!(model)

Xpress.writebasis(backend(model).inner, “basis.bas”, “”)

model = create_optimization_problem()

Xpress.readbasis(backend(model).inner, “basis.bas”, “”)

@time optimize!(model)