remove optimality assertions, add comment

Author: Joao-Dionisio

src/pyscipopt/lp.pxi

@@ -373,19 +373,21 @@ cdef class LP:
         return SCIPlpiIsOptimal(self.lpi)
 
     def getObjVal(self):
-        """Returns the objective value of the last LP solve."""
-        assert self.isOptimal(), "LP is not optimal"
-
+        """
+        Returns the objective value of the last LP solve.
+        Please note that infeasible or unbounded LPs might return unexpected results.
+        """
         cdef SCIP_Real objval
 
         PY_SCIP_CALL(SCIPlpiGetSol(self.lpi, &objval, NULL, NULL, NULL, NULL))
 
         return objval
 
     def getPrimal(self):
-        """Returns the primal solution of the last LP solve."""
-        assert self.isOptimal(), "LP is not optimal"
-
+        """
+        Returns the primal solution of the last LP solve.
+        Please note that infeasible or unbounded LPs might return unexpected results.
+        """
         cdef int ncols = self.ncols()
         cdef SCIP_Real* c_primalsol = <SCIP_Real*> malloc(ncols * sizeof(SCIP_Real))
         cdef int i
@@ -403,9 +405,10 @@ cdef class LP:
         return SCIPlpiIsPrimalFeasible(self.lpi)
 
     def getDual(self):
-        """Returns the dual solution of the last LP solve."""
-        assert self.isOptimal(), "LP is not optimal"
-
+        """
+        Returns the dual solution of the last LP solve.
+        Please note that infeasible or unbounded LPs might return unexpected results.
+        """
         cdef int nrows = self.nrows()
         cdef SCIP_Real* c_dualsol = <SCIP_Real*> malloc(nrows * sizeof(SCIP_Real))
         cdef int i
@@ -471,9 +474,10 @@ cdef class LP:
         return niters
 
     def getActivity(self):
-        """Returns the row activity vector of the last LP solve."""
-        assert self.isOptimal(), "LP is not optimal"
-
+        """
+        Returns the row activity vector of the last LP solve.
+        Please note that infeasible or unbounded LPs might return unexpected results.
+        """
         cdef int nrows = self.nrows()
         cdef SCIP_Real* c_activity = <SCIP_Real*> malloc(nrows * sizeof(SCIP_Real))
         cdef int i
@@ -489,9 +493,10 @@ cdef class LP:
         return activity
 
     def getRedcost(self):
-        """Returns the reduced cost vector of the last LP solve."""
-        assert self.isOptimal(), "LP is not optimal"
-
+        """
+        Returns the reduced cost vector of the last LP solve.
+        Please note that infeasible or unbounded LPs might return unexpected results.
+        """
         cdef int ncols = self.ncols()
         cdef SCIP_Real* c_redcost = <SCIP_Real*> malloc(ncols * sizeof(SCIP_Real))
         cdef int i