Esempio n. 1
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    def test_merge(self):
        """Test merging functions.
        """
        # sum_entries
        x = Variable(10)
        fn1 = sum_entries(x, gamma=1.0)
        fn2 = norm1(x)
        assert can_merge(fn1, fn2)
        merged = merge_fns(fn1, fn2)
        v = np.arange(10) * 1.0 - 5.0
        prox_val1 = merged.prox(1.0, v.copy())
        tmp = norm1(x, c=np.ones(10), gamma=1.0)
        prox_val2 = tmp.prox(1.0, v.copy())
        self.assertItemsAlmostEqual(prox_val1, prox_val2)

        # sum_squares
        x = Variable(10)
        val = np.arange(10)
        fn1 = sum_squares(x, gamma=1.0, beta=2.0, alpha=3.0, b=val)
        fn2 = norm1(x)
        assert can_merge(fn1, fn2)
        merged = merge_fns(fn1, fn2)
        v = np.arange(10) * 1.0 - 5.0
        prox_val1 = merged.prox(1.0, v.copy())
        tmp = norm1(x, c=-12 * val, gamma=1.0 + 12, d=val.dot(val))
        prox_val2 = tmp.prox(1.0, v.copy())
        self.assertItemsAlmostEqual(prox_val1, prox_val2)
Esempio n. 2
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    def test_merge(self):
        """Test merging functions.
        """
        # sum_entries
        x = Variable(10)
        fn1 = sum_entries(x, gamma=1.0)
        fn2 = norm1(x)
        assert can_merge(fn1, fn2)
        merged = merge_fns(fn1, fn2)
        v = np.arange(10) * 1.0 - 5.0
        prox_val1 = merged.prox(1.0, v.copy())
        tmp = norm1(x, c=np.ones(10), gamma=1.0)
        prox_val2 = tmp.prox(1.0, v.copy())
        self.assertItemsAlmostEqual(prox_val1, prox_val2)

        # sum_squares
        x = Variable(10)
        val = np.arange(10)
        fn1 = sum_squares(x, gamma=1.0, beta=2.0, alpha=3.0, b=val)
        fn2 = norm1(x)
        assert can_merge(fn1, fn2)
        merged = merge_fns(fn1, fn2)
        v = np.arange(10) * 1.0 - 5.0
        prox_val1 = merged.prox(1.0, v.copy())
        tmp = norm1(x, c=-12 * val, gamma=1.0 + 12, d=val.dot(val))
        prox_val2 = tmp.prox(1.0, v.copy())
        self.assertItemsAlmostEqual(prox_val1, prox_val2)
Esempio n. 3
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 def test_sum_entries(self):
     """Sum of entries of lin op.
     """
     tmp = Variable(10)
     v = np.arange(10) * 1.0 - 5.0
     fn = sum_entries(tmp)
     x = fn.prox(1.0, v.copy())
     self.assertItemsAlmostEqual(x, v - 1)
Esempio n. 4
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 def test_sum_entries(self):
     """Sum of entries of lin op.
     """
     tmp = Variable(10)
     v = np.arange(10) * 1.0 - 5.0
     fn = sum_entries(tmp)
     x = fn.prox(1.0, v.copy())
     self.assertItemsAlmostEqual(x, v - 1)
Esempio n. 5
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 def test_merge_all(self):
     """Test function to merge all prox operators possible.
     """
     # merge all
     x = Variable(10)
     lin_op = grad(x)
     fns = [sum_squares(lin_op), sum_entries(lin_op), nonneg(lin_op)]
     merged = merge_all(fns)
     assert len(merged) == 1
     v = np.reshape(np.arange(10) * 1.0 - 5.0, (10, 1))
     prox_val1 = merged[0].prox(1.0, v.copy())
     tmp = nonneg(lin_op, c=np.ones((10, 1)), gamma=1.0)
     prox_val2 = tmp.prox(1.0, v.copy())
     self.assertItemsAlmostEqual(prox_val1, prox_val2)
Esempio n. 6
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 def test_merge_all(self):
     """Test function to merge all prox operators possible.
     """
     # merge all
     x = Variable(10)
     lin_op = grad(x)
     fns = [sum_squares(lin_op), sum_entries(lin_op), nonneg(lin_op)]
     merged = merge_all(fns)
     assert len(merged) == 1
     v = np.reshape(np.arange(10) * 1.0 - 5.0, (10, 1))
     prox_val1 = merged[0].prox(1.0, v.copy())
     tmp = nonneg(lin_op, c=np.ones((10, 1)), gamma=1.0)
     prox_val2 = tmp.prox(1.0, v.copy())
     self.assertItemsAlmostEqual(prox_val1, prox_val2)
Esempio n. 7
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    def test_absorb_lin_op(self):
        """Test absorb lin op operator.
        """
        # norm1.
        tmp = Variable(10)
        v = np.arange(10) * 1.0 - 5.0

        fn = norm1(mul_elemwise(-v, tmp), alpha=5.)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())
        self.assertItemsAlmostEqual(x, np.sign(v) * np.maximum(np.abs(v) - 5. *
                                                               np.abs(v) / rho, 0))

        fn = norm1(mul_elemwise(-v, mul_elemwise(2 * v, tmp)), alpha=5.)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())
        self.assertItemsAlmostEqual(x, np.sign(v) * np.maximum(np.abs(v) - 5. *
                                                               np.abs(v) / rho, 0))
        new_prox = absorb_lin_op(new_prox)[0]
        x = new_prox.prox(rho, v.copy())
        new_v = 2 * v * v
        self.assertItemsAlmostEqual(x, np.sign(new_v) *
                                    np.maximum(np.abs(new_v) - 5. * np.abs(new_v) / rho, 0))

        # nonneg.
        tmp = Variable(10)
        v = np.arange(10) * 1.0 - 5.0

        fn = nonneg(mul_elemwise(-v, tmp), alpha=5.)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())
        self.assertItemsAlmostEqual(x, fn.prox(rho, -np.abs(v)))

        # sum_squares.
        tmp = Variable(10)
        v = np.arange(10) * 1.0 - 5.0

        alpha = 5.
        val = np.arange(10)
        fn = sum_squares(mul_elemwise(-v, tmp), alpha=alpha, c=val)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())

        cvx_x = cvx.Variable(10)
        prob = cvx.Problem(cvx.Minimize(cvx.sum_squares(cvx_x - v) * (rho / 2) +
                                        5 * cvx.sum_squares(cvx.mul_elemwise(-v,
                                                            cvx_x)) + (val * -v).T * cvx_x
                                        ))
        prob.solve()
        self.assertItemsAlmostEqual(x, cvx_x.value, places=3)

        # Test scale.
        tmp = Variable(10)
        v = np.arange(10) * 1.0 - 5.0

        fn = norm1(10 * tmp)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())
        cvx_x = cvx.Variable(10)
        prob = cvx.Problem(cvx.Minimize(cvx.sum_squares(cvx_x - v) + cvx.norm(10 * cvx_x, 1)))
        prob.solve()
        self.assertItemsAlmostEqual(x, cvx_x.value, places=3)

        val = np.arange(10)
        fn = norm1(10 * tmp, c=val, b=val, gamma=0.01)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())
        cvx_x = cvx.Variable(10)
        prob = cvx.Problem(cvx.Minimize(cvx.sum_squares(cvx_x - v) +
                                        cvx.norm(10 * cvx_x - val, 1) + 10 * val.T * \
                                                 cvx_x + cvx.sum_squares(cvx_x)
                                        ))
        prob.solve()
        self.assertItemsAlmostEqual(x, cvx_x.value, places=2)

        # sum_entries
        tmp = Variable(10)
        v = np.arange(10) * 1.0 - 5.0

        fn = sum_entries(sum([10 * tmp, mul_elemwise(v, tmp)]))

        funcs = absorb.absorb_all_lin_ops([fn])
        c = __builtins__['sum']([func.c for func in funcs])
        self.assertItemsAlmostEqual(c, v + 10, places=3)
Esempio n. 8
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    def test_absorb_lin_op(self):
        """Test absorb lin op operator.
        """
        # norm1.
        tmp = Variable(10)
        v = np.arange(10) * 1.0 - 5.0

        fn = norm1(mul_elemwise(-v, tmp), alpha=5.)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())
        self.assertItemsAlmostEqual(
            x,
            np.sign(v) * np.maximum(np.abs(v) - 5. * np.abs(v) / rho, 0))

        fn = norm1(mul_elemwise(-v, mul_elemwise(2 * v, tmp)), alpha=5.)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())
        self.assertItemsAlmostEqual(
            x,
            np.sign(v) * np.maximum(np.abs(v) - 5. * np.abs(v) / rho, 0))
        new_prox = absorb_lin_op(new_prox)[0]
        x = new_prox.prox(rho, v.copy())
        new_v = 2 * v * v
        self.assertItemsAlmostEqual(
            x,
            np.sign(new_v) *
            np.maximum(np.abs(new_v) - 5. * np.abs(new_v) / rho, 0))

        # nonneg.
        tmp = Variable(10)
        v = np.arange(10) * 1.0 - 5.0

        fn = nonneg(mul_elemwise(-v, tmp), alpha=5.)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())
        self.assertItemsAlmostEqual(x, fn.prox(rho, -np.abs(v)))

        # sum_squares.
        tmp = Variable(10)
        v = np.arange(10) * 1.0 - 5.0

        alpha = 5.
        val = np.arange(10)
        fn = sum_squares(mul_elemwise(-v, tmp), alpha=alpha, c=val)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())

        cvx_x = cvx.Variable(10)
        prob = cvx.Problem(
            cvx.Minimize(
                cvx.sum_squares(cvx_x - v) * (rho / 2) +
                5 * cvx.sum_squares(cvx.mul_elemwise(-v, cvx_x)) +
                (val * -v).T * cvx_x))
        prob.solve()
        self.assertItemsAlmostEqual(x, cvx_x.value, places=3)

        # Test scale.
        tmp = Variable(10)
        v = np.arange(10) * 1.0 - 5.0

        fn = norm1(10 * tmp)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())
        cvx_x = cvx.Variable(10)
        prob = cvx.Problem(
            cvx.Minimize(cvx.sum_squares(cvx_x - v) + cvx.norm(10 * cvx_x, 1)))
        prob.solve()
        self.assertItemsAlmostEqual(x, cvx_x.value, places=3)

        val = np.arange(10)
        fn = norm1(10 * tmp, c=val, b=val, gamma=0.01)
        rho = 2
        new_prox = absorb_lin_op(fn)[0]
        x = new_prox.prox(rho, v.copy())
        cvx_x = cvx.Variable(10)
        prob = cvx.Problem(cvx.Minimize(cvx.sum_squares(cvx_x - v) +
                                        cvx.norm(10 * cvx_x - val, 1) + 10 * val.T * \
                                                 cvx_x + cvx.sum_squares(cvx_x)
                                        ))
        prob.solve()
        self.assertItemsAlmostEqual(x, cvx_x.value, places=2)

        # sum_entries
        tmp = Variable(10)
        v = np.arange(10) * 1.0 - 5.0

        fn = sum_entries(sum([10 * tmp, mul_elemwise(v, tmp)]))

        funcs = absorb.absorb_all_lin_ops([fn])
        c = __builtins__['sum']([func.c for func in funcs])
        self.assertItemsAlmostEqual(c, v + 10, places=3)