removing value errors when declaring multiple attributes

cvxpy/expressions/leaf.py

@@ -142,15 +142,6 @@ def __init__(
         else:
             self.integer_idx = []
 
-        # Only one attribute be True (except can be boolean and integer).
-        true_attr = sum(1 for k, v in self.attributes.items() if v)
-        # HACK we should remove this feature or allow multiple attributes in general.
-        if boolean and integer:
-            true_attr -= 1
-        if true_attr > 1:
-            raise ValueError("Cannot set more than one special attribute in %s."
-                             % self.__class__.__name__)
-
         if value is not None:
             self.value = value
 

cvxpy/tests/test_expressions.py

@@ -15,6 +15,7 @@
 """
 
 import warnings
+from itertools import combinations
 
 import numpy as np
 import pytest
@@ -68,8 +69,6 @@ def test_variable(self) -> None:
         self.assertEqual(x.shape, (2,))
         self.assertEqual(y.shape, tuple())
         self.assertEqual(x.curvature, s.AFFINE)
-        # self.assertEqual(x.canonical_form[0].shape, (2, 1))
-        # self.assertEqual(x.canonical_form[1], [])
 
         self.assertEqual(repr(self.x), "Variable((2,), x)")
         self.assertEqual(repr(self.A), "Variable((2, 2), A)")
@@ -79,11 +78,6 @@ def test_variable(self) -> None:
         # Test shape provided as list instead of tuple
         self.assertEqual(cp.Variable(shape=[2], integer=True).shape, (2,))
 
-        with self.assertRaises(Exception) as cm:
-            Variable((2, 2), diag=True, symmetric=True)
-        self.assertEqual(str(cm.exception),
-                         "Cannot set more than one special attribute in Variable.")
-
         with self.assertRaises(Exception) as cm:
             Variable((2, 0))
         self.assertEqual(str(cm.exception), "Invalid dimensions (2, 0).")
@@ -450,11 +444,6 @@ def test_parameters_failures(self) -> None:
             p = Parameter((4, 3), nonneg=True, value=[1, 2])
         self.assertEqual(str(cm.exception), "Invalid dimensions (2,) for Parameter value.")
 
-        with self.assertRaises(Exception) as cm:
-            p = Parameter((2, 2), diag=True, symmetric=True)
-        self.assertEqual(str(cm.exception),
-                         "Cannot set more than one special attribute in Parameter.")
-
         # Boolean
         with self.assertRaises(Exception) as cm:
             p = Parameter((2, 2), boolean=True, value=[[1, 1], [1, -1]])
@@ -1621,3 +1610,31 @@ def is_zero_dim_output(axis):
         prob = cp.Problem(self.obj, [expr == y])
         prob.solve(canon_backend=cp.SCIPY_CANON_BACKEND)
         assert np.allclose(expr.value, y)
+
+class Test_Attributes():
+
+    def test_multiple_attributes(self) -> None:
+        x = cp.Variable(shape=(2,2), symmetric=True, nonneg=True, integer=True, boolean=True)
+        target = np.array(np.eye(2))
+        prob = cp.Problem(cp.Minimize(0), [x == target])
+        prob.solve()
+        assert np.allclose(x.value, target)
+
+    # Define the attributes to test
+    attributes = [
+    'nonneg', 'pos', 'nonpos', 'neg', 'diag', 'PSD', 'NSD', 'imag', 'boolean', 'integer'
+    ]
+
+    # Generate combinations of attributes
+    combinations_of_attributes = []
+    for r in range(1, len(attributes) + 1):
+        combinations_of_attributes.extend(combinations(attributes, r))
+
+    @pytest.mark.parametrize("attributes", combinations_of_attributes)
+    def test_variable_combinations(self, attributes):
+        kwargs = {attr: True for attr in attributes}
+        var = cp.Variable(shape=(2, 2), **kwargs)
+        target = np.array([[0, 1], [1, 0]])
+        prob = cp.Problem(cp.Minimize(0), [var == target])
+        prob.solve()
+        assert np.allclose(var.value, target)