Implement TravelingSalesmanPerturber

tests/fixtures/gen_tsp.py

@@ -7,6 +7,7 @@ from miplearn.collectors.basic import BasicCollector
 from miplearn.io import write_pkl_gz
 from miplearn.problems.tsp import (
     TravelingSalesmanGenerator,
+    TravelingSalesmanPerturber,
     build_tsp_model_gurobipy,
     build_tsp_model_pyomo,
 )
@@ -16,12 +17,19 @@ gen = TravelingSalesmanGenerator(
     x=uniform(loc=0.0, scale=1000.0),
     y=uniform(loc=0.0, scale=1000.0),
     n=randint(low=20, high=21),
-    gamma=uniform(loc=1.0, scale=0.25),
-    fix_cities=True,
+    gamma=uniform(loc=1.0, scale=0.0),
     round=True,
 )
 
-data = gen.generate(3)
+# Generate a reference instance with fixed cities
+reference_instance = gen.generate(1)[0]
+
+# Generate perturbed instances with same cities but different distance scaling
+perturber = TravelingSalesmanPerturber(
+    gamma=uniform(loc=1.0, scale=0.25),
+    round=True,
+)
+data = perturber.perturb(reference_instance, 3)
 
 params = {"seed": 42, "threads": 1}