add method for MOI.EqualTo{Float64} set

[jd-lara]

The previous implementation called Lib.XPRSchgbounds(), Ref(value)) twice once for L and once for B. This implied that when calling JuMP.fix() Xpress would throw warnings if a previous UB or LB was above or below the new value. In large model it would generate a lot of noise in the logging.

This PR employs Lib.XPRSchgbounds(model.inner, Cint(1), Ref(Cint(info.column-1)), Ref(UInt8('B')), Ref(value)) in a new method for attempts to fix the variable and remove the warning calls.

[joaquimg]

I have been talking about similar things with @guilhermebodin , lets us take a look.

[jd-lara]

FYI the tests are failing due to: ERROR: LoadError: InitError: Xpress licensing error 10: Your license expired on 31-oct-2022. Please contact support@fico.com to renew it.

[joaquimg]

The main issue is that _set_variable_lower_bound doe more than just calling XPRSchgbounds. So we need to protect against those cases because the equality change end up changing the LB. Needs something more carefully written. Also if tests passed locally, the are not capturing this corner case that might require a model with a SOC.

[joaquimg]

FYI the tests are failing due to: ERROR: LoadError: InitError: Xpress licensing error 10: Your license expired on 31-oct-2022. Please contact support@fico.com to renew it.

Thank we will update.

[jd-lara]

The main issue is that _set_variable_lower_bound doe more than just calling XPRSchgbounds. So we need to protect against those cases because the equality change end up changing the LB. Needs something more carefully written. Also if tests passed locally, the are not capturing this corner case that might require a model with a SOC.

We can add the check let me try something.

[jd-lara]

@joaquimg check this commit 7ca6e4b

[jd-lara]

local tests outcomes

[jd-lara]

bump to @odow and @joaquimg.

[joaquimg]

on it!

[joaquimg]

replaced by #187