Uploaded Test files

venv/Lib/site-packages/sklearn/utils/tests/test_optimize.py

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+import numpy as np
+
+from sklearn.utils.optimize import _newton_cg
+from scipy.optimize import fmin_ncg
+
+from sklearn.utils._testing import assert_array_almost_equal
+
+
+def test_newton_cg():
+    # Test that newton_cg gives same result as scipy's fmin_ncg
+
+    rng = np.random.RandomState(0)
+    A = rng.normal(size=(10, 10))
+    x0 = np.ones(10)
+
+    def func(x):
+        Ax = A.dot(x)
+        return .5 * (Ax).dot(Ax)
+
+    def grad(x):
+        return A.T.dot(A.dot(x))
+
+    def hess(x, p):
+        return p.dot(A.T.dot(A.dot(x.all())))
+
+    def grad_hess(x):
+        return grad(x), lambda x: A.T.dot(A.dot(x))
+
+    assert_array_almost_equal(
+        _newton_cg(grad_hess, func, grad, x0, tol=1e-10)[0],
+        fmin_ncg(f=func, x0=x0, fprime=grad, fhess_p=hess)
+        )