Emma Johnson

GDPopt rewrite!

4

## Fixes # ## Summary/Motivation: This is a rewrite of GDPopt with the goal of improving extensibility and maintainability. ## Changes proposed in this PR: - Removes gdpbb--it has been...

## Summary Right now it is often necessary to preprocess a model before solving it to deactivate an constraints that may have become trivially satisfied after fixing variables. (This is...

## Summary Currently, there is no solver-agnostic way to specify a solver time limit in Pyomo. This leads to a lot of `if` trees in packages like `gdpopt` and `mindtpy`...

GDPopt LBB doesn't solve trivial GDP

1

## Summary The GDPopt LBB algorithm does not find a solution for a problem where the Boolean solution is already fixed. ### Steps to reproduce the issue ``` m =...

## Summary The GDP transformations create weakrefs, meaning that transformed models are currently unpickleable.

## Summary References to ConstraintDatas in ConstraintLists die on a TypeError. ConstraintDatas of other IndexedConstraints seem okay. ### Steps to reproduce the issue ``` from pyomo.environ import * m =...

## Summary The `_generate_additively_separable_repn` function used in `gdp.partition_disjuncts` handles only the easiest case where the expression in question is a `SumExpression`. There are a lot of other cases that we...

## Summary The `contrib.propagate_fixed_vars` transformation is not wrong, but it misses some constraints which set a variable equal to a constant. ### Steps to reproduce the issue This example is...

## Summary The `contrib.propagate_fixed_vars` transformation should find all constraints of the form `x == y` where one of `x` or `y` is fixed, and fix the other accordingly. However, in...

Can't solve subblock with gurobi_direct

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## Summary Hopefully this isn't a duplicate issue, but it is not possible to solve a ScalarBlock with `gurobi_direct`. ### Steps to reproduce the issue ``` from pyomo.environ import *...