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                                            Jason Sherman

Example in PyROS docs doesn't use solver of the correct class

PyROS has not yet been tested for two-stage robust MINLPs; per the [documentation](https://pyomo.readthedocs.io/en/stable/contributed_packages/pyros.html#methodology-overview), the current implementation only provides support for models with continuous variables (robust NLPs). If you are looking...

Example in PyROS docs doesn't use solver of the correct class

PyROS currently supports sets for which all parameters are discrete, or all parameters are continuous; to my knowledge, sets with both discrete and continuous parameters have not yet been tested....

Example in PyROS docs doesn't use solver of the correct class

@makansij I currently have access to COUENNE through the [IDAES Toolkit](https://github.com/IDAES/idaes-pse), which itself can be installed using the [instructions here](https://idaes-pse.readthedocs.io/en/1.4.4/install/index.html). @jsiirola Do you know any simple methods for installing COUENNE...

Example in PyROS docs doesn't use solver of the correct class

@makansij I believe the issue is due to the note shown below step 2 of the installation instructions (binary extensions not yet supported for Mac)

Solver returns “A feasible solution was not found, so no solution can be loaded”, even though a feasible solution is clearly available.

@makansij: 1. Just to be clear, have you confirmed that your solution is _robust_ feasible (i.e. feasible for your model constraints under _all_ parameter realizations in the uncertainty set you...

Solver returns “A feasible solution was not found, so no solution can be loaded”, even though a feasible solution is clearly available.

@makansij 1. If you know in advance (via formal proof) that your model solution (and therefore your RO model) is robust feasible, then we would hope that PyROS successfully either...

Solver returns “A feasible solution was not found, so no solution can be loaded”, even though a feasible solution is clearly available.

Looks like your local solver could not find a feasible solution to the master problem of iteration 5. It's possible that this master problem is indeed infeasible (and hence your...

Solver returns “A feasible solution was not found, so no solution can be loaded”, even though a feasible solution is clearly available.

@makansij - As per the [documentation](https://pyomo.readthedocs.io/en/latest/contributed_packages/pyros.html#pyomo.contrib.pyros.PyROS), the option `load_solution` only dictates whether PyROS should load any solutions found by the end of the PyROS algorithm. Moreover, if `load_solution` is set...

Solver returns “A feasible solution was not found, so no solution can be loaded”, even though a feasible solution is clearly available.

Are you actually referring to NaN (as in `float("nan")` or `numpy.nan`), or do you mean `None`? I don't expect a first-stage variable value in the solution returned by PyROS to...

Solver returns “A feasible solution was not found, so no solution can be loaded”, even though a feasible solution is clearly available.

Hi @makansij: 1. It is possible that the model is robust feasible or robust infeasible. You could say that the model is "locally robust infeasible", but this concept is currently...