problems: Allow correlated arguments in random problem generators

tests/problems/test_setpack.py

@@ -3,9 +3,11 @@
 #  Released under the modified BSD license. See COPYING.md for more details.
 
 import numpy as np
+from scipy.stats import randint, uniform
 
 from miplearn.problems.setpack import (
     SetPackData,
+    SetPackGenerator,
     build_setpack_model_gurobipy,
 )
 
@@ -24,3 +26,19 @@ def test_setpack() -> None:
     model = build_setpack_model_gurobipy(data)
     model.optimize()
     assert model.inner.objval == -22.0
+
+
+def test_set_pack_generator_callable() -> None:
+    np.random.seed(42)
+    gen = SetPackGenerator(
+        n_elements=randint(low=4, high=5),
+        n_sets=lambda n: n * 2,
+        costs=uniform(loc=10.0, scale=0.0),
+        density=uniform(loc=0.5, scale=0),
+        K=uniform(loc=0, scale=0),
+    )
+    data = gen.generate(1)
+    n_elements, n_sets = data[0].incidence_matrix.shape
+    assert n_elements == 4
+    assert n_sets == 8
+    assert len(data[0].costs) == 8