Merge pull request #3965 from jsiirola/cplex-iis

Fix IIS interface for current CPLEX releases

Author: jsiirola

.github/workflows/test_branches.yml

@@ -320,14 +320,7 @@ jobs:
         python -m pip install --cache-dir cache/pip pymysql || \
             python -m pip install --cache-dir cache/pip pymysql
         if test -z "${{matrix.slim}}"; then
-            # Disallow cplex 22.1.2.1 because it errors fatally when
-            #  computing IIS on python 3.13 and 3.14
-            if [[ ${{matrix.python}} =~ 3.1[34] ]]; then
-                CPLEX='cplex!=22.1.2.1'
-            else
-                CPLEX='cplex'
-            fi
-            python -m pip install --cache-dir cache/pip "$CPLEX" docplex \
+            python -m pip install --cache-dir cache/pip cplex docplex \
                 || echo "WARNING: CPLEX Community Edition is not available"
             python -m pip install --cache-dir cache/pip gurobipy \
                 || echo "WARNING: Gurobi is not available"
@@ -410,14 +403,8 @@ jobs:
             PYVER=$(echo "py${{matrix.python}}" | sed 's/\.//g')
             echo "Installing for $PYVER"
             #
-            # Disallow cplex 22.1.2 and 22.1.2.1, as they error fatally when
-            #   computing IIS on Python 3.13 and 3.14
             # Disallow cplex 12.9 (caused segfaults in tests)
-            if [[ ${{matrix.python}} =~ 3.1[34] ]]; then
-                CPLEX='cplex>=12.10,<22.1.2|>22.1.2.1'
-            else
-                CPLEX='cplex>=12.10'
-            fi
+            CPLEX='cplex>=12.10'
             # xpress.init() (xpress 9.5.1 from conda) hangs indefinitely
             # on GHA/Windows under Python 3.10 and 3.11.  Exclude that
             # release on that platform.

.github/workflows/test_pr_and_main.yml

@@ -373,14 +373,7 @@ jobs:
         python -m pip install --cache-dir cache/pip pymysql || \
             python -m pip install --cache-dir cache/pip pymysql
         if test -z "${{matrix.slim}}"; then
-            # Disallow cplex 22.1.2.1 because it errors fatally when
-            #  computing IIS on python 3.13 and 3.14
-            if [[ ${{matrix.python}} =~ 3.1[34] ]]; then
-                CPLEX='cplex!=22.1.2.1'
-            else
-                CPLEX='cplex'
-            fi
-            python -m pip install --cache-dir cache/pip "$CPLEX" docplex \
+            python -m pip install --cache-dir cache/pip cplex docplex \
                 || echo "WARNING: CPLEX Community Edition is not available"
             python -m pip install --cache-dir cache/pip gurobipy \
                 || echo "WARNING: Gurobi is not available"
@@ -463,14 +456,8 @@ jobs:
             PYVER=$(echo "py${{matrix.python}}" | sed 's/\.//g')
             echo "Installing for $PYVER"
             #
-            # Disallow cplex 22.1.2 and 22.1.2.1, as they error fatally when
-            #   computing IIS on Python 3.13 and 3.14
             # Disallow cplex 12.9 (caused segfaults in tests)
-            if [[ ${{matrix.python}} =~ 3.1[34] ]]; then
-                CPLEX='cplex>=12.10,<22.1.2|>22.1.2.1'
-            else
-                CPLEX='cplex>=12.10'
-            fi
+            CPLEX='cplex>=12.10'
             # xpress.init() (xpress 9.5.1 from conda) hangs indefinitely
             # on GHA/Windows under Python 3.10 and 3.11.  Exclude that
             # release on that platform.

pyomo/contrib/iis/iis.py

@@ -104,7 +104,8 @@ def write(self, file_name):
 
 class CplexConflict(_IISBase):
     def compute(self):
-        self._solver._solver_model.conflict.refine()
+        _conflict = self._solver._solver_model.conflict
+        _conflict.refine(_conflict.all_constraints())
 
     def write(self, file_name):
         self._solver._solver_model.conflict.write(file_name)