added div and some other small changes

Author: dance858

cvxpy/atoms/affine/binary_operators.py

@@ -404,6 +404,9 @@ def is_decr(self, idx) -> bool:
             return self.args[1].is_nonpos()
         else:
             return self.args[0].is_nonneg()
+    
+    def point_in_domain(self):
+        return np.ones(self.args[1].shape)
 
     def graph_implementation(
         self, arg_objs, shape: Tuple[int, ...], data=None

cvxpy/reductions/expr2smooth/canonicalizers/__init__.py

@@ -19,6 +19,8 @@
 from cvxpy.atoms.elementwise.power import power
 from cvxpy.atoms.pnorm import Pnorm
 from cvxpy.atoms.elementwise.abs import abs
+from cvxpy.atoms.affine.binary_operators import DivExpression
+from cvxpy.reductions.expr2smooth.canonicalizers.div_canon import div_canon
 from cvxpy.reductions.expr2smooth.canonicalizers.log_canon import log_canon
 from cvxpy.reductions.expr2smooth.canonicalizers.minimum_canon import minimum_canon
 from cvxpy.reductions.expr2smooth.canonicalizers.abs_canon import abs_canon
@@ -33,5 +35,5 @@
     log: log_canon,
     power: power_canon,
     Pnorm : pnorm_canon,
-    # inv: inv_pos_canon,
+    DivExpression: div_canon,       
 }

cvxpy/reductions/expr2smooth/canonicalizers/div_canon.py

@@ -0,0 +1,26 @@
+"""
+Copyright 2025 CVXPY developers
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+"""
+
+from cvxpy.expressions.variable import Variable
+
+
+def div_canon(expr, args):
+    denom = Variable(args[1].shape)
+    if args[1].value is not None:
+        denom.value = args[1].value
+    else:
+        denom.value = expr.point_in_domain()
+    return expr.copy([args[0], denom]), [denom == args[1]]

cvxpy/reductions/expr2smooth/canonicalizers/log_canon.py

@@ -19,5 +19,8 @@
 
 def log_canon(expr, args):
     t = Variable(args[0].size)
-    t.value = expr.point_in_domain()
+    if args[0].value is not None:
+        t.value = args[0].value
+    else:
+        t.value = expr.point_in_domain()
     return expr.copy([t]), [t==args[0]]

cvxpy/reductions/expr2smooth/canonicalizers/power_canon.py

@@ -36,12 +36,13 @@ def power_canon(expr, args):
         t = Variable(shape)
         if 0 < p < 1:
             if x.value is not None:
+                # TODO: check if this initialization is correct
                 t.value = np.power(np.abs(x.value), p)
             return t, [t**(1/p) == x, t >= 0]
         elif p > 1:
             t = Variable(args[0].shape)
             if args[0].value is not None:
-                t.value = np.power(args[0].value, p)
+                t.value = args[0].value
             else:
                 t.value = expr.point_in_domain()
             return expr.copy([t]), [t==args[0]]