Summary/Motivation:

Upon the solution of a separation problem, PyROS attempts to evaluate the violations of all second-stage inequality constraints at the optimal solution to that separation problem. In (rare) cases, the evaluation may fail due to an exception encountered/raised by the Pyomo expression evaluators. This exception may be of type ValueError or ArithmeticError. Currently, PyROS does not handle an exception of type ArithmeticError and handles a ValueError-type exception as follows:

• Issue INFO-level logging messages reporting the names and values of all first-stage variables and second-stage variables of the separation model
• Raise an ArithmeticError with a message of the form "Evaluation . . . of constraint . . . led to a math domain error. Does the constraint contain . . . functions . . . with tricky domains?"

In this PR, we modify PyROS to handle an exception of type ValueError or ArithmeticError as follows:

• Issue an ERROR-level logging message reporting that PyROS encountered an evaluation error, and including the names and values of all variables of the separation model (including variables representing uncertain parameters) that appear in the expression
• Reraise the exception

Changes proposed in this PR:

See above.

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