MNT clean up old scipy sparse.linalg.cg fallback code (scikit-learn#26813)

lesteve · punndcoder28 · commit b0a5ee5638c6 · 2023-07-29T17:38:00.000+05:30
diff --git a/sklearn/linear_model/_ridge.py b/sklearn/linear_model/_ridge.py
@@ -105,12 +105,7 @@ def _mv(x):
             C = sp_linalg.LinearOperator(
                 (n_samples, n_samples), matvec=mv, dtype=X.dtype
             )
-            # FIXME atol
-            try:
-                coef, info = sp_linalg.cg(C, y_column, tol=tol, atol="legacy")
-            except TypeError:
-                # old scipy
-                coef, info = sp_linalg.cg(C, y_column, tol=tol)
+            coef, info = sp_linalg.cg(C, y_column, tol=tol, atol="legacy")
             coefs[i] = X1.rmatvec(coef)
         else:
             # linear ridge
@@ -119,14 +114,9 @@ def _mv(x):
             C = sp_linalg.LinearOperator(
                 (n_features, n_features), matvec=mv, dtype=X.dtype
             )
-            # FIXME atol
-            try:
-                coefs[i], info = sp_linalg.cg(
-                    C, y_column, maxiter=max_iter, tol=tol, atol="legacy"
-                )
-            except TypeError:
-                # old scipy
-                coefs[i], info = sp_linalg.cg(C, y_column, maxiter=max_iter, tol=tol)
+            coefs[i], info = sp_linalg.cg(
+                C, y_column, maxiter=max_iter, tol=tol, atol="legacy"
+            )
 
         if info < 0:
             raise ValueError("Failed with error code %d" % info)
