Julian Hall comments

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                                            Julian Hall

IPX Mods

IPX now appears to have presolve, so changes are meaningful

The optimal solution ultimately found has bugs

Thanks @tusiqi1

Compiling with -fPIC flag required for highspy package?

Thanks for this @bpampel, perhaps it will be valuable for @galabovaa

Assertion `new_infeasibility < 0' failed in HEkkPrimal.cpp:2813: void HEkkPrimal::shiftBound()

Thanks, I'll take a look in due course

Assertion `new_infeasibility < 0' failed in HEkkPrimal.cpp:2813: void HEkkPrimal::shiftBound()

I'll look at it, but will have to be sure that it doesn't lead to other problems or impair general performance

Naked assert in latest branch

Indeed, setting `presolve=off` is a radical solution. The assert that you've hit shouldn't matter, in that when compiling in release the case is still handled. It's a developer's assert, and...

Strange bug in solving a QP model

Thanks for this. Our QP developer will investigate

Strange bug in solving a QP model

> Of course! At the moment I'm collaborating in the development of a modeling system named [SMS++](https://smspp.gitlab.io/smspp-project/). In particular, I have worked in building the interface to allow users to...

instance found to be infeasible but it isn't if run without presolve or run with cbc

Thanks. I've reproduced this behaviour. I'll ask the developer of our MIP presolve/solver to look into it.

instance found to be infeasible but it isn't if run without presolve or run with cbc

> On my side the optimal solution is also found when I reduce the value for option 'small_matrix_value'. That's interesting. This option was set up to filter small values from...