def test_dcp_curvature(self):
expr = 1 + cvx.exp(cvx.Variable())
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.Parameter()*cvx.Variable(nonneg=True)
self.assertEqual(expr.curvature, s.AFFINE)
f = lambda x: x**2 + x**0.5 # noqa E731
expr = f(cvx.Constant(2))
self.assertEqual(expr.curvature, s.CONSTANT)
expr = cvx.exp(cvx.Variable())**2
self.assertEqual(expr.curvature, s.CONVEX)
expr = 1 - cvx.sqrt(cvx.Variable())
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.log(cvx.sqrt(cvx.Variable()))
self.assertEqual(expr.curvature, s.CONCAVE)
expr = -(cvx.exp(cvx.Variable()))**2
self.assertEqual(expr.curvature, s.CONCAVE)
expr = cvx.log(cvx.exp(cvx.Variable()))
self.assertEqual(expr.is_dcp(), False)
expr = cvx.entr(cvx.Variable(nonneg=True))
self.assertEqual(expr.curvature, s.CONCAVE)
expr = ((cvx.Variable()**2)**0.5)**0
self.assertEqual(expr.curvature, s.CONSTANT)
def test_dcp_curvature(self):
expr = 1 + cvx.exp(cvx.Variable())
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.Parameter()*cvx.NonNegative()
self.assertEqual(expr.curvature, s.AFFINE)
f = lambda x: x**2 + x**0.5
expr = f(cvx.Constant(2))
self.assertEqual(expr.curvature, s.CONSTANT)
expr = cvx.exp(cvx.Variable())**2
self.assertEqual(expr.curvature, s.CONVEX)
expr = 1 - cvx.sqrt(cvx.Variable())
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.log( cvx.sqrt(cvx.Variable()) )
self.assertEqual(expr.curvature, s.CONCAVE)
expr = -( cvx.exp(cvx.Variable()) )**2
self.assertEqual(expr.curvature, s.CONCAVE)
expr = cvx.log( cvx.exp(cvx.Variable()) )
self.assertEqual(expr.is_dcp(), False)
expr = cvx.entr( cvx.NonNegative() )
self.assertEqual(expr.curvature, s.CONCAVE)
expr = ( (cvx.Variable()**2)**0.5 )**0
self.assertEqual(expr.curvature, s.CONSTANT)
def test_exp(self) -> None:
"""Test domain for exp.
"""
expr = cp.exp(self.a)
self.a.value = 2
self.assertAlmostEqual(expr.grad[self.a], np.exp(2))
self.a.value = 3
self.assertAlmostEqual(expr.grad[self.a], np.exp(3))
self.a.value = -1
self.assertAlmostEqual(expr.grad[self.a], np.exp(-1))
expr = cp.exp(self.x)
self.x.value = [3, 4]
val = np.zeros((2, 2)) + np.diag(np.exp([3, 4]))
self.assertItemsAlmostEqual(expr.grad[self.x].toarray(), val)
expr = cp.exp(self.x)
self.x.value = [-1e-9, 4]
val = np.zeros((2, 2)) + np.diag(np.exp([-1e-9, 4]))
self.assertItemsAlmostEqual(expr.grad[self.x].toarray(), val)
expr = cp.exp(self.A)
self.A.value = [[1, 2], [3, 4]]
val = np.zeros((4, 4)) + np.diag(np.exp([1, 2, 3, 4]))
self.assertItemsAlmostEqual(expr.grad[self.A].toarray(), val)
def test_exp(self):
x = cp.Variable(4, pos=True)
c = cp.Parameter(4, pos=True)
expr = cp.exp(cp.multiply(c, x))
self.assertTrue(expr.is_dgp(dpp=True))
expr = cp.exp(c.T @ x)
self.assertTrue(expr.is_dgp(dpp=True))
def simple_convex_alogrithm(z_minus_u, alpha, weight, UENum, minReward=0.0):
# Do not use numpy when you use cvxopt!!!!!!!!!!@@@@################################################################
x = cp.Variable(UENum)
y = [weight[i] * (x[i]**float(alpha[i]))/alpha[i] for i in range(UENum)]
const = [(x[i]**float(alpha[i]))/alpha[i] for i in range(UENum)] # the requirement only for real reward (not weighted)
if use_other_utility_function:
y = [weight[i] * RESNum/(RESNum * cp.exp(- alpha[i] * x[i]) + 1) for i in range(UENum)]
const = [ RESNum/(RESNum * cp.exp(- alpha[i] * x[i])+ 1) for i in range(UENum)]
fx = cp.sum(y) - 0.5 * rho * cp.sum_squares(cp.sum(x) - z_minus_u)
objective = cp.Minimize(-fx)
factor, iter, maxiter = 1, 1, 10 # decrease the factor, i.e., loose the constraint, when we cannot solve the problem optimally
# solve the problem, if not optimal or not well solved, reduce the constraint and do it again
while True:
constraints = [factor*minReward <= const[i] for i in range(UENum)] + [cp.sum(x) <= Rmax]
prob = cp.Problem(objective, constraints,)
# The optimal objective value is returned by `prob.solve()`.
result = prob.solve() #gp=True
assert(iter <= maxiter)
if prob.status == 'optimal':
break
else:
factor *= 0.5
iter += 1
optimal_x = x.value
utility, real_utility, const_ = np.zeros(UENum), np.zeros(UENum), np.zeros(UENum)
for i in range(UENum):
const_[i] = (optimal_x[i]**alpha[i])/alpha[i]
utility[i] = weight[i] * (optimal_x[i]**alpha[i])/alpha[i] - maxTime * np.clip(minReward - const_[i], 0, None)
real_utility[i] = weight[i] * (optimal_x[i]**alpha[i])/alpha[i]
if use_other_utility_function:
const_[i] = Rmax/(Rmax * np.exp(- alpha[i] * optimal_x[i])+ 1)
utility[i] = weight[i] * Rmax/(Rmax * np.exp(- alpha[i] * optimal_x[i])+ 1) - maxTime * np.clip(minReward - const_[i], 0, None)
real_utility[i] = weight[i] * Rmax/(Rmax * np.exp(- alpha[i] * optimal_x[i])+ 1)
aug_penalty = 0.5 * rho * np.abs(np.sum(optimal_x) - z_minus_u)
# The optimal value for x is stored in `x.value`.
return np.sum(utility)-aug_penalty, optimal_x, np.sum(real_utility)
def to_cvx(self, f, scale=1.0):
yi = f(self.x[0])
yj = f(self.x[1])
yk = f(self.x[2])
diff1 = yk - yj + eps
#diff2 = yk - yi + eps
diff2 = yk + yj - 2 * yi
exp1 = 1 - cvx.exp(-scale * diff1)
exp2 = 1 - cvx.exp(-scale * diff2)
val = cvx.min_elemwise(exp1, exp2)
log_val = -cvx.log(val)
return log_val, [diff1 > eps, diff2 > eps]
def switch(self):
if self.phi_name == 'logistic':
self.cvx_phi = lambda z: cvx.logistic(-z) # / math.log(2, math.e)
elif self.phi_name == 'hinge':
self.cvx_phi = lambda z: cvx.pos(1 - z)
elif self.phi_name == 'squared':
self.cvx_phi = lambda z: cvx.square(-z)
elif self.phi_name == 'exponential':
self.cvx_phi = lambda z: cvx.exp(-z)
else:
logger.error('%s is not include' % self.phi_name)
logger.info('Logistic is the default setting')
self.cvx_phi = lambda z: cvx.logistic(-z) # / math.log(2, math.e)
if self.kappa_name == 'logistic':
self.cvx_kappa = lambda z: cvx.logistic(z) # / math.log(2, math.e)
self.psi_kappa = lambda mu: ((1 + mu) * math.log(1 + mu) +
(1 - mu) * math.log(3 - mu)) / 2
elif self.kappa_name == 'hinge':
self.cvx_kappa = lambda z: cvx.pos(1 + z)
self.psi_kappa = lambda mu: mu
elif self.kappa_name == 'squared':
self.cvx_kappa = lambda z: cvx.square(1 + z)
self.psi_kappa = lambda mu: mu**2
elif self.kappa_name == 'exponential':
self.cvx_kappa = lambda z: cvx.exp(z)
self.psi_kappa = lambda mu: 1 - math.sqrt(1 - mu**2)
else:
logger.error('%s is not include' % self.kappa_name)
logger.info('hinge is the default setting')
self.cvx_kappa = lambda z: cvx.pos(1 + z)
self.psi_kappa = lambda mu: mu
if self.delta_name == 'logistic':
self.cvx_delta = lambda z: 1 - cvx.logistic(
-z) # / math.log(2, math.e)
self.psi_delta = lambda mu: ((1 + mu) * math.log(1 + mu) +
(1 - mu) * math.log(1 - mu)) / 2
elif self.delta_name == 'hinge':
self.cvx_delta = lambda z: 1 - cvx.pos(1 - z)
self.psi_delta = lambda mu: mu
elif self.delta_name == 'squared':
self.cvx_delta = lambda z: 1 - cvx.square(1 - z)
self.psi_delta = lambda mu: mu**2
elif self.delta_name == 'exponential':
self.cvx_delta = lambda z: 1 - cvx.exp(-z)
self.psi_delta = lambda mu: 1 - math.sqrt(1 - mu**2)
else:
logger.error('%s is not include' % self.delta_name)
logger.info('hinge is the default setting')
self.cvx_delta = lambda z: cvx.pos(1 + z)
self.psi_delta = lambda mu: mu
def test_expcone_1(self):
x = cvx.Variable(shape=(1, ))
tempcons = [cvx.exp(x[0]) <= np.exp(1), cvx.exp(-x[0]) <= np.exp(1)]
sigma = cvx.suppfunc(x, tempcons)
y = cvx.Variable(shape=(1, ))
obj_expr = y[0]
cons = [sigma(y) <= 1]
# ^ That just means -1 <= y[0] <= 1
prob = cvx.Problem(cvx.Minimize(obj_expr), cons)
prob.solve(solver='ECOS')
viol = cons[0].violation()
assert viol <= 1e-6
assert abs(y.value - (-1)) <= 1e-6
def test_expcone_1(self) -> None:
x = cp.Variable(shape=(1, ))
tempcons = [cp.exp(x[0]) <= np.exp(1), cp.exp(-x[0]) <= np.exp(1)]
sigma = cp.suppfunc(x, tempcons)
y = cp.Variable(shape=(1, ))
obj_expr = y[0]
cons = [sigma(y) <= 1]
# ^ That just means -1 <= y[0] <= 1
prob = cp.Problem(cp.Minimize(obj_expr), cons)
prob.solve(solver='ECOS')
viol = cons[0].violation()
self.assertLessEqual(viol, 1e-6)
self.assertLessEqual(abs(y.value - (-1)), 1e-6)
def test_partial_optimize_special_constr(self):
x, y = Variable(1), Variable(1)
# Solve the (simple) two-stage problem by "combining" the two stages
# (i.e., by solving a single linear program)
p1 = Problem(Minimize(x + cp.exp(y)), [x + y >= 3, y >= 4, x >= 5])
p1.solve()
# Solve the two-stage problem via partial_optimize
p2 = Problem(Minimize(cp.exp(y)), [x + y >= 3, y >= 4])
g = partial_optimize(p2, [y], [x])
p3 = Problem(Minimize(x + g), [x >= 5])
p3.solve()
self.assertAlmostEqual(p1.value, p3.value)
def generate_cvx(cls, constraints, f, transform=None, scale=1.0):
x, x_low, x_high = ConvexNeighborConstraint.generate_neighbors_for_scipy_optimize(
constraints, transform)
yi = f(x)
yj = f(x_low)
yk = f(x_high)
diff1 = yk - yj
#diff2 = yk - yi
diff2 = yk + yj - 2 * yi
exp1 = 1 - cvx.exp(-scale * diff1) + eps
exp2 = 1 - cvx.exp(-scale * diff2) + eps
val = cvx.min_elemwise(exp1, exp2)
log_val = -cvx.log(val)
sum_val = cvx.sum_entries(log_val)
return sum_val, [diff1 > eps, diff2 > eps]
def test_signed_curvature(self):
# Convex argument.
expr = cvx.abs(1 + cvx.exp(cvx.Variable()) )
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.abs( -cvx.entr(cvx.Variable()) )
self.assertEqual(expr.curvature, s.UNKNOWN)
expr = cvx.abs( -cvx.log(cvx.Variable()) )
self.assertEqual(expr.curvature, s.UNKNOWN)
# Concave argument.
expr = cvx.abs( cvx.log(cvx.Variable()) )
self.assertEqual(expr.curvature, s.UNKNOWN)
expr = cvx.abs( -cvx.square(cvx.Variable()) )
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.abs( cvx.entr(cvx.Variable()) )
self.assertEqual(expr.curvature, s.UNKNOWN)
# Affine argument.
expr = cvx.abs( cvx.NonNegative() )
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.abs( -cvx.NonNegative() )
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.abs( cvx.Variable() )
self.assertEqual(expr.curvature, s.CONVEX)
def _solve_balancing_cvx(J0, cost_fn, factors=None, **solve_args):
"""
Use CVXPY to solve the synaptic balancing problem.
This is very fast on small matrices (<100 neurons), but quite slow on
larger matrices.
arguments:
J0 is N x N numpy array
arguments:
J0 is N x N numpy array
cost_fn is CostFunction instance
returns: summarized transform
"""
import cvxpy as cvx
# define constant element-wise weights
J0 = np.array(J0).astype(float)
weights = cost_fn.alpha * (np.abs(J0)**cost_fn.p)
# define variable (state, h, and the log ratio matrix derived from it)
N = J0.shape[0]
h = cvx.Variable((N, 1), value=np.zeros((N, 1)))
log_ratios = -h * np.ones((1, N)) + np.ones((N, 1)) * h.T
C = cvx.multiply(weights, cvx.exp(cost_fn.p * log_ratios))
# solve problem and get final transform vector
problem = cvx.Problem(cvx.Minimize(cvx.sum(C)))
problem.solve(**solve_args)
hf = h.value[:, 0]
# report results
return summarize_transform(J0, cost_fn, hf)
def find_optimal_dosage(A, D, x, m=3, n=4):
z = np.log10(np.array(x))
# treatment concentration vectors
u = cp.Variable((m, 1))
# Perron-Frobenius eigenvalue of ODE system
lambda_pf = cp.Variable((1, 1))
# Minimize the Perron-Frobenius eigenvalue to maximize rate of viral decay
objective = cp.Minimize(lambda_pf)
constraints = []
# Treatment concentrations must be non-negative and lie in unit simplex
constraints.append(u >= 0)
constraints.append(sum(u) == 1)
for k in range(n):
constraints.append(
A[k, :] @ cp.exp(z - z[k]) + D[k, :] @ u <= lambda_pf)
problem = cp.Problem(objective, constraints)
result = problem.solve()
return lambda_pf, u
def test_key_error(self):
"""Test examples that caused key error.
"""
import cvxpy as cvx
x = cvx.Variable()
u = -cvx.exp(x)
prob = cvx.Problem(cvx.Maximize(u), [x == 1])
prob.solve(verbose=True, solver=cvx.CVXOPT)
prob.solve(verbose=True, solver=cvx.CVXOPT)
###########################################
import numpy as np
import cvxopt
import cvxpy as cp
kD=2
Sk=cp.semidefinite(kD)
Rsk=cp.Parameter(kD,kD)
mk=cp.Variable(kD,1)
musk=cp.Parameter(kD,1)
logpart=-0.5*cp.log_det(Sk)+0.5*cp.matrix_frac(mk,Sk)+(kD/2.)*np.log(2*np.pi)
linpart=mk.T*musk-0.5*cp.trace(Sk*Rsk)
obj=logpart-linpart
prob=cp.Problem(cp.Minimize(obj))
musk.value=np.ones((2,1))
covsk=np.diag([0.3,0.5])
Rsk.value=covsk+(musk.value*musk.value.T)
prob.solve(verbose=True,solver=cp.CVXOPT)
print "second solve"
prob.solve(verbose=False, solver=cp.CVXOPT)
def test_key_error(self):
"""Test examples that caused key error.
"""
if cvx.CVXOPT in cvx.installed_solvers():
x = cvx.Variable()
u = -cvx.exp(x)
prob = cvx.Problem(cvx.Maximize(u), [x == 1])
prob.solve(verbose=True, solver=cvx.CVXOPT)
prob.solve(verbose=True, solver=cvx.CVXOPT)
###########################################
import numpy as np
kD = 2
Sk = cvx.Variable((kD, kD), PSD=True)
Rsk = cvx.Parameter((kD, kD))
mk = cvx.Variable((kD, 1))
musk = cvx.Parameter((kD, 1))
logpart = -0.5 * cvx.log_det(Sk) + 0.5 * cvx.matrix_frac(
mk, Sk) + (kD / 2.) * np.log(2 * np.pi)
linpart = mk.T * musk - 0.5 * cvx.trace(Sk * Rsk)
obj = logpart - linpart
prob = cvx.Problem(cvx.Minimize(obj), [Sk == Sk.T])
musk.value = np.ones((2, 1))
covsk = np.diag([0.3, 0.5])
Rsk.value = covsk + (musk.value * musk.value.T)
prob.solve(verbose=True, solver=cvx.CVXOPT)
print("second solve")
prob.solve(verbose=False, solver=cvx.CVXOPT)
def test_multiply_nonlinear_nonneg_param_and_nonneg_variable_is_not_dpp(
self):
x = cp.Parameter(nonneg=True)
y = cp.Variable(nonneg=True)
product = cp.exp(x) * y
self.assertFalse(product.is_dpp())
self.assertTrue(product.is_dcp())
def test_tutorial_example(self):
x = cp.Variable()
y = cp.Variable(pos=True)
objective_fn = -cp.sqrt(x) / y
problem = cp.Problem(cp.Minimize(objective_fn), [cp.exp(x) <= y])
# smoke test
problem.solve(SOLVER, qcp=True)
def test_signed_curvature(self):
# Convex argument.
expr = cvx.abs(1 + cvx.exp(cvx.Variable()))
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.abs(-cvx.entr(cvx.Variable()))
self.assertEqual(expr.curvature, s.UNKNOWN)
expr = cvx.abs(-cvx.log(cvx.Variable()))
self.assertEqual(expr.curvature, s.UNKNOWN)
# Concave argument.
expr = cvx.abs(cvx.log(cvx.Variable()))
self.assertEqual(expr.curvature, s.UNKNOWN)
expr = cvx.abs(-cvx.square(cvx.Variable()))
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.abs(cvx.entr(cvx.Variable()))
self.assertEqual(expr.curvature, s.UNKNOWN)
# Affine argument.
expr = cvx.abs(cvx.Variable(nonneg=True))
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.abs(-cvx.Variable(nonneg=True))
self.assertEqual(expr.curvature, s.CONVEX)
expr = cvx.abs(cvx.Variable())
self.assertEqual(expr.curvature, s.CONVEX)
def test_multiply_param_and_nonlinear_variable_is_dpp(self):
x = cp.Parameter(nonneg=True)
y = cp.Variable()
product = x * cp.exp(y)
self.assertTrue(product.is_convex())
self.assertTrue(product.is_dcp())
self.assertTrue(product.is_dpp())
def test_warm_start(self):
if cp.SUPER_SCS in INSTALLED_SOLVERS:
x = cp.Variable(10)
obj = cp.Minimize(cp.sum(cp.exp(x)))
prob = cp.Problem(obj, [cp.sum(x) == 1])
result = prob.solve(solver='SUPER_SCS', eps=1e-4)
result2 = prob.solve(solver='SUPER_SCS', warm_start=True, eps=1e-4)
self.assertAlmostEqual(result2, result, places=2)
def test_paper_example_exp_log(self):
x = cvxpy.Variable(pos=True)
y = cvxpy.Variable(pos=True)
obj = cvxpy.Minimize(x * y)
constr = [cvxpy.exp(y / x) <= cvxpy.log(y)]
problem = cvxpy.Problem(obj, constr)
# smoke test.
problem.solve(SOLVER, gp=True)
def solve_g_dual_cp(C, a, b, eta, tau):
u = cp.Variable(shape=a.shape)
v = cp.Variable(shape=b.shape)
u_stack = cp.vstack([u.T for _ in range(nr)])
v_stack = cp.hstack([v for _ in range(nc)])
print(u_stack.shape, v_stack.shape)
# obj = eta * cp.sum(cp.multiply(cp.exp(u + v.T) * cp.exp(v).T, 1 / cp.exp(C)))
# obj = eta * cp.sum(cp.multiply(cp.exp(u_stack + v_stack), 1 / cp.exp(C)))
obj = eta * cp.sum(cp.exp((u_stack + v_stack - C) / eta))
obj += tau * cp.sum(cp.multiply(cp.exp(-u / tau), a))
obj += tau * cp.sum(cp.multiply(cp.exp(-v / tau), b))
prob = cp.Problem(cp.Minimize(obj))
prob.solve()
return prob.value, u.value, v.value
def choose_phi(self, phi_name):
if phi_name == 'logistic':
self.cvx_phi = lambda z: cvx.logistic(-z)
elif phi_name == 'hinge':
self.cvx_phi = lambda z: cvx.pos(1.0 - z)
elif phi_name == 'exponential':
self.cvx_phi = lambda z: cvx.exp(-z)
else:
print("Your surrogate function doesn't exist.")
def cvx_hw2(A, b, x):
x = cp.Variable(len(x), value=x.reshape(-1, ))
prob = cp.Problem(cp.Minimize(cp.sum(cp.exp(A @ x - b.squeeze()))))
prob.solve()
# print(prob.value)
# Print result.
x = x.value
return x
def running_constraints(constr, config, x, u, gam, z, dt, N):
A_w = create_A(config.w)
alpha = 1.0 / (config.isp * 9.8)
pointing_angle = np.cos(config.pointing_lim)
p1 = config.p1
p2 = config.p2
v_max = config.v_max
c = get_cone(config.landing_cone)
g = config.g
# Simple Euler integration
for k in range(N - 1):
# Rocket dynamics constraints
constr += [x[0:3, k + 1] == x[0:3, k] + dt * (A_w @ x[:, k])[0:3]]
constr += [x[3:6, k + 1] == x[3:6, k] + dt * (g + u[:, k])]
constr += [z[k + 1] == z[k] - dt * alpha * gam[k]]
constr += [cvp.norm(x[3:6, k]) <= v_max
] # Velocity remains below maximum
constr += [
cvp.norm(u[:, k]) <= gam[k]
] # Helps enforce the magnitude of thrust vector == thrust magnitude
constr += [u[0, k] >= pointing_angle * gam[k]
] # Rocket can only point away from vertical by so much
constr += [
cvp.norm(_E @ (x[:3, k] - x[:3, -1])) -
c.T @ (x[:3, k] - x[:3, -1]) <= 0
] # Stay inside the glide cone
if k > 0:
z_0 = cvp.log(config.m - alpha * p2 * (k) * dt)
z_1 = cvp.log(config.m - alpha * p1 * (k) * dt)
sigma_lower = p1 * cvp.exp(-z_0) * (1 - (z[k] - z_0) +
(z[k] - z_0))
sigma_upper = p2 * cvp.exp(-z_0) * (1 - (z[k] - z_0))
# Minimimum and maximum thrust constraints
constr += [gam[k] <= sigma_upper]
constr += [gam[k] >= sigma_lower]
# Minimum and maximum mass constraints
constr += [z[k] >= z_0]
constr += [z[k] <= z_1]
return constr
def test_exp(self):
"""Test a problem with exp.
"""
for n in [5, 10, 25]:
print(n)
x = cp.Variable(n)
obj = cp.Minimize(cp.sum(cp.exp(x)))
p = cp.Problem(obj, [cp.sum(x) == 1])
p.solve(solver=cp.SCS)
self.assertItemsAlmostEqual(x.value, n*[1./n])
def test_paper_example_exp_log(self) -> None:
x = cp.Variable(pos=True)
y = cp.Variable(pos=True)
a = cp.Parameter(pos=True, value=0.2)
b = cp.Parameter(pos=True, value=0.3)
obj = cp.Minimize(x * y)
constr = [cp.exp(a * y / x) <= cp.log(b * y)]
problem = cp.Problem(obj, constr)
gradcheck(problem, gp=True, atol=1e-2)
perturbcheck(problem, gp=True, atol=1e-2)
def test_warm_start(self):
"""Test warm starting.
"""
if cvx.SUPER_SCS in cvx.installed_solvers():
x = cvx.Variable(10)
obj = cvx.Minimize(cvx.sum(cvx.exp(x)))
prob = cvx.Problem(obj, [cvx.sum(x) == 1])
result = prob.solve(solver='SUPER_SCS', eps=1e-4)
result2 = prob.solve(solver='SUPER_SCS', warm_start=True, eps=1e-4)
self.assertAlmostEqual(result2, result, places=2)
def fit(self, warm_start=True, label=None, save=False,
use_glmnet=False, use_cvxpy=False, cvxpy_tol=1e-4,
**kwargs):
'''
Note: use_cvxpy or use_glmnet only works with CV weights (i.e. all 0 or 1)
'''
if not use_cvxpy and not use_glmnet:
super(ExponentialPoissonRegressionModel, self).fit(warm_start,
label,
save,
**kwargs)
elif use_glmnet:
from glmnet_py import glmnet
lambdau = np.array([self.L1Lambda,])
inds = self.example_weights.astype(np.bool)
x = self.training_data.X[inds,:].copy()
y = self.training_data.Y[inds].copy().astype(np.float)
fit = glmnet(x=x,
y=y,
family='poisson',
standardize=False,
lambdau=lambdau,
thresh=1e-20,
maxit=10e4,
alpha=1.0,
)
elif use_cvxpy:
import cvxpy
D = self.params.get_free().shape[0]
Ntrain = self.training_data.X.shape[0]
theta = cvxpy.Variable(D, value=self.params.get_free())
weights = self.example_weights
X = self.training_data.X
Y = self.training_data.Y
obj = cvxpy.Minimize(-Y*cvxpy.multiply(weights,(X*(theta)))
+ cvxpy.sum(cvxpy.multiply(weights, cvxpy.exp(X*(theta))))
+ self.L1Lambda * cvxpy.sum(cvxpy.abs((theta)[:-1]))
)
problem = cvxpy.Problem(obj)
problem.solve(solver=cvxpy.SCS, normalize=True,
eps=cvxpy_tol, verbose=False, max_iters=2000)
if (problem.status == 'infeasible_inaccurate' or
problem.status == 'unbounded_inaccurate'):
problem.solve(solver=cvxpy.SCS, normalize=True,
eps=cvxpy_tol, verbose=False, max_iters=2000)
problem.solve(solver=cvxpy.SCS, normalize=True,
eps=cvxpy_tol, verbose=False, max_iters=10000)
try:
self.params.set_free(theta.value)
except:
print('Bad problem?', problem.status)
def test_warm_start(self):
"""Test warm starting.
"""
x = cvx.Variable(10)
obj = cvx.Minimize(cvx.sum(cvx.exp(x)))
prob = cvx.Problem(obj, [cvx.sum(x) == 1])
result = prob.solve(solver=cvx.SCS, eps=1e-4)
time = prob.solver_stats.solve_time
result2 = prob.solve(solver=cvx.SCS, warm_start=True, eps=1e-4)
time2 = prob.solver_stats.solve_time
self.assertAlmostEqual(result2, result, places=2)
def test_exp(self):
"""Test a problem with exp.
"""
if cvx.SUPER_SCS in cvx.installed_solvers():
for n in [5, 10, 25]:
print(n)
x = cvx.Variable(n)
obj = cvx.Minimize(cvx.sum(cvx.exp(x)))
p = cvx.Problem(obj, [cvx.sum(x) == 1])
p.solve(solver='SUPER_SCS', verbose=True)
self.assertItemsAlmostEqual(x.value, n*[1./n])
def train(self, level=0, lamb=0.01):
"""
:param level: 0: 非正则化; 1: 1阶正则化; 2: 2阶正则化
:param lamb: 正则化系数水平
:return: 无
"""
L = cvx.Parameter(sign="positive")
L.value = lamb # 正则化系数
w = cvx.Variable(self.n + 1) # 参数向量
loss = 0
for i in range(self.m): # 构造成本函数和正则化项
loss += self.y_trans[i] * \
cvx.log_sum_exp(cvx.vstack(0, cvx.exp(self.x_trans[i, :].T * w))) + \
(1 - self.y_trans[i]) * \
cvx.log_sum_exp(cvx.vstack(0, cvx.exp(-1 * self.x_trans[i, :].T * w)))
# 为什么一定要用log_sum_exp? cvx.log(1 + cvx.exp(x[i, :].T * w))为什么不行?
if level > 0:
reg = cvx.norm(w[:self.n], level)
prob = cvx.Problem(cvx.Minimize(loss / self.m + L / (2 * self.m) * reg))
else:
prob = cvx.Problem(cvx.Minimize(loss / self.m))
prob.solve()
self.w = np.array(w.value)
def FindKineticOptimum(self, bounds=None):
"""Use the power of convex optimization!
minimize sum (protein cost)
we can do this by using ln(concentration) as variables and leveraging
the convexity of exponentials.
"""
assert self.dG0_f_prime is not None
ln_conc, constraints = self._MakeMinimumFeasbileConcentrationsProblem()
total_inv_conc = cvxpy.sum(cvxpy.exp(-ln_conc))
program = cvxpy.program(cvxpy.minimize(total_inv_conc), constraints)
program.solve(quiet=True)
return ln_conc.value, total_inv_conc.value
def poisson_loss(theta, X, y):
return (cp.sum_entries(cp.exp(X*theta)) -
cp.sum_entries(sp.diags([y],[0])*X*theta))
prox("NON_NEGATIVE", None, C_non_negative_scaled),
prox("NON_NEGATIVE", None, C_non_negative_scaled_elemwise),
prox("NON_NEGATIVE", None, lambda: [x >= 0]),
prox("NORM_1", f_norm1_weighted),
prox("NORM_1", lambda: cp.norm1(x)),
prox("NORM_2", lambda: cp.norm(X, "fro")),
prox("NORM_2", lambda: cp.norm2(x)),
prox("NORM_NUCLEAR", lambda: cp.norm(X, "nuc")),
prox("SECOND_ORDER_CONE", None, C_soc_scaled),
prox("SECOND_ORDER_CONE", None, C_soc_scaled_translated),
prox("SECOND_ORDER_CONE", None, C_soc_translated),
prox("SECOND_ORDER_CONE", None, lambda: [cp.norm(X, "fro") <= t]),
prox("SECOND_ORDER_CONE", None, lambda: [cp.norm2(x) <= t]),
prox("SEMIDEFINITE", None, lambda: [X >> 0]),
prox("SUM_DEADZONE", f_dead_zone),
prox("SUM_EXP", lambda: cp.sum_entries(cp.exp(x))),
prox("SUM_HINGE", f_hinge),
prox("SUM_HINGE", lambda: cp.sum_entries(cp.max_elemwise(1-x, 0))),
prox("SUM_HINGE", lambda: cp.sum_entries(cp.max_elemwise(1-x, 0))),
prox("SUM_INV_POS", lambda: cp.sum_entries(cp.inv_pos(x))),
prox("SUM_KL_DIV", lambda: cp.sum_entries(cp.kl_div(p1,q1))),
prox("SUM_LARGEST", lambda: cp.sum_largest(x, 4)),
prox("SUM_LOGISTIC", lambda: cp.sum_entries(cp.logistic(x))),
prox("SUM_NEG_ENTR", lambda: cp.sum_entries(-cp.entr(x))),
prox("SUM_NEG_LOG", lambda: cp.sum_entries(-cp.log(x))),
prox("SUM_QUANTILE", f_quantile),
prox("SUM_QUANTILE", f_quantile_elemwise),
prox("SUM_SQUARE", f_least_squares_matrix),
prox("SUM_SQUARE", lambda: f_least_squares(20)),
prox("SUM_SQUARE", lambda: f_least_squares(5)),
prox("SUM_SQUARE", f_quad_form),
import numpy as np
import cvxpy as cp
from matrix_equilibration_data import *
import numpy.linalg as la
B = np.square(A)
u = cp.Variable(m)
v = cp.Variable(n)
Be = 0
for i in xrange(m):
for j in xrange(n):
Be += cp.exp(cp.log(B[i, j]) + u[i] + v[j])
obj = cp.Minimize(Be)
cons = [cp.sum_entries(u) == 1, cp.sum_entries(v) == 1]
prob = cp.Problem(obj, cons)
prob.solve()
D = np.zeros((m, m))
for i in xrange(m):
D[i, i] = np.exp(u.value[i, 0] / p)
E = np.zeros((n, n))
for i in xrange(n):
E[i, i] = np.exp(v.value[i, 0] / p)
A_equi = np.dot(np.dot(D, A), E)
print "2-norm for every row:"
for i in xrange(m):
print la.norm(A_equi[i, :])
1.7095 2.1351 10.1296 4.0931 2.9001 9.9634;\
1.4289 3.5800 9.3459 3.8898 2.7663 15.1383;\
1.3046 3.5610 10.1179 4.3891 7.1302 3.8139;\
1.1897 2.7807 13.0112 4.2426 6.1611 29.6734'
W = np.matrix(W)
(W_min, W_max) = (1.0, 30.0)
# objective values for the different designs
# entry j gives the objective for design j
P = np.matrix('29.0148 46.3369 282.1749 78.5183 104.8087 253.5439')
D = np.matrix('15.9522 11.5012 4.8148 8.5697 8.0870 6.0273')
A = np.matrix('22.3796 38.7908 204.1574 62.5563 81.2272 200.5119')
# specifications
(P_spec, D_spec, A_spec) = (60.0, 10.0, 50.0)
theta = cvx.Variable(k)
obj = cvx.Minimize(0)
constraints = [cvx.log(P)*theta <= cvx.log(P_spec),
cvx.log(D)*theta <= cvx.log(D_spec),
cvx.log(A)*theta <= cvx.log(A_spec),
cvx.sum_entries(theta) == 1, theta >= 0]
prob = cvx.Problem(obj, constraints)
sol = prob.solve()
w = cvx.exp(cvx.log(W)*theta)
print('status: {}'.format(sol))
print('theta: {}'.format(theta.T.value))
print('w: {}'.format(w.T.value))
def MinimizeConcentration(self, metabolite_index=None,
concentration_bounds=None):
"""Finds feasible concentrations minimizing the concentration
of metabolite i.
Args:
metabolite_index: the index of the metabolite to minimize.
if == None, minimize the sum of all concentrations.
concentration_bounds: the Bounds objects setting concentration bounds.
"""
my_bounds = concentration_bounds or self.DefaultConcentrationBounds()
ln_conc = cvxpy.variable(m=1, n=self.Ncompounds, name='lnC')
ln_conc_lb, ln_conc_ub = my_bounds.GetLnBounds(self.compounds)
constr = [cvxpy.geq(ln_conc, cvxpy.matrix(ln_conc_lb)),
cvxpy.leq(ln_conc, cvxpy.matrix(ln_conc_ub))]
my_dG0_r_primes = np.matrix(self.dG0_r_prime)
# Make flux-based constraints on reaction free energies.
# All reactions must have negative dGr in the direction of the flux.
# Reactions with a flux of 0 must be in equilibrium.
S = np.matrix(self.S)
for i, flux in enumerate(self.fluxes):
curr_dg0 = my_dG0_r_primes[0, i]
# if the dG0 is unknown, this reaction imposes no new constraints
if np.isnan(curr_dg0):
continue
rcol = cvxpy.matrix(S[:, i])
curr_dgr = curr_dg0 + RT * ln_conc * rcol
if flux == 0:
constr.append(cvxpy.eq(curr_dgr, 0.0))
else:
constr.append(cvxpy.leq(curr_dgr, 0.0))
objective = None
if metabolite_index is not None:
my_conc = ln_conc[0, metabolite_index]
objective = cvxpy.minimize(cvxpy.exp(my_conc))
else:
objective = cvxpy.minimize(
cvxpy.sum(cvxpy.exp(ln_conc)))
name = 'CONC_OPT'
if metabolite_index:
name = 'CONC_%d_OPT' % metabolite_index
problem = cvxpy.program(objective, constr, name=name)
optimum = problem.solve(quiet=True)
"""
status = problem.solve(quiet=True)
if status != 'optimal':
status = optimized_pathway.OptimizationStatus.Infeasible(
'Pathway infeasible given bounds.')
return ConcentrationOptimizedPathway(
self._model, self._thermo,
my_bounds, optimization_status=status)
"""
opt_ln_conc = np.matrix(np.array(ln_conc.value))
result = ConcentrationOptimizedPathway(
self._model, self._thermo,
my_bounds, optimal_value=optimum,
optimal_ln_metabolite_concentrations=opt_ln_conc)
return result
#!/usr/bin/env python
import numpy as np
import cvxpy as cp
from epopt import cvxpy_expr
from epopt import expression_vis
from epopt.compiler import canonicalize
if __name__ == "__main__":
n = 5
x = cp.Variable(n)
# Lasso expression tree
m = 10
A = np.random.randn(m,n)
b = np.random.randn(m)
lam = 1
f = cp.sum_squares(A*x - b) + lam*cp.norm1(x)
prob0 = cvxpy_expr.convert_problem(cp.Problem(cp.Minimize(f)))[0]
expression_vis.graph(prob0.objective).write("expr_lasso.dot")
# Canonicalization of a more complicated example
c = np.random.randn(n)
f = cp.exp(cp.norm(x) + c.T*x) + cp.norm1(x)
prob0 = cvxpy_expr.convert_problem(cp.Problem(cp.Minimize(f)))[0]
expression_vis.graph(prob0.objective).write("expr_epigraph.dot")
prob1 = canonicalize.transform(prob0)
expression_vis.graph(prob1.objective).write("expr_epigraph_canon.dot")