aboutsummaryrefslogtreecommitdiffstats
path: root/src/convex_optimization.py
diff options
context:
space:
mode:
authorjeanpouget-abadie <jean.pougetabadie@gmail.com>2015-02-01 13:43:12 -0500
committerjeanpouget-abadie <jean.pougetabadie@gmail.com>2015-02-01 13:43:12 -0500
commit0991a13214af4023259465f132f09e6c66f3895c (patch)
tree4c3f89721285eb07a004e8efae9375f3dbd4919e /src/convex_optimization.py
parent6446b4bc986be1e4ff4bd1914efc4a2e6d0b7d12 (diff)
downloadcascades-0991a13214af4023259465f132f09e6c66f3895c.tar.gz
remodeling results section
Diffstat (limited to 'src/convex_optimization.py')
-rw-r--r--src/convex_optimization.py72
1 files changed, 13 insertions, 59 deletions
diff --git a/src/convex_optimization.py b/src/convex_optimization.py
index 96dc26f..2661e25 100644
--- a/src/convex_optimization.py
+++ b/src/convex_optimization.py
@@ -6,63 +6,9 @@ import timeout
import cvxopt
-@timeout.timeout(20)
-def l1obj_l2constraint(M_val, w_val):
- """
- Solves:
- min - sum_j theta_j
- s.t theta_j <= 0
- |e^{M*theta} - (1 - w)|_2 <= 1
- """
- assert len(M_val) == len(w_val)
-
- if M_val.dtype == bool:
- M_val = M_val.astype('float32')
-
- m, n = M_val.shape
- c = cvxopt.matrix(-1.0, (n,1))
-
- theta = tensor.row().T
- z = tensor.row().T
- theta_ = theta.flatten()
- z_ = z.flatten()
- M = theano.shared(M_val.astype(theano.config.floatX))
- w = theano.shared(w_val.astype(theano.config.floatX))
- y = (tensor.exp(M.dot(theta_)) - (1 - w)).norm(2) - 1
- y_diff = tensor.grad(y, theta_)
- y_hess = z[0] * theano.gradient.hessian(y, theta_)
- f_x = theano.function([theta], [y, y_diff], allow_input_downcast=True)
- f_xz = theano.function([theta, z], [y, y_diff, y_hess],
- allow_input_downcast=True)
-
- def F(x=None, z=None):
- if x is None:
- return 1, cvxopt.matrix(.0001, (n,1))
- elif z is None:
- y, y_diff = f_x(x)
- return cvxopt.matrix(float(y), (1, 1)),\
- cvxopt.matrix(y_diff.astype("float64")).T
- else:
- y, y_diff, y_hess = f_xz(x, z)
- return cvxopt.matrix(float(y), (1, 1)), \
- cvxopt.matrix(y_diff.astype("float64")).T, \
- cvxopt.matrix(y_hess.astype("float64"))
-
- G = cvxopt.spdiag([1 for i in xrange(n)])
- h = cvxopt.matrix(0.0, (n,1))
-
- cvxopt.solvers.options['show_progress'] = False
- try:
- theta = cvxopt.solvers.cpl(c,F, G, h)['x']
- except ArithmeticError:
- print "ArithmeticError thrown, change initial point"+\
- " given to the solver"
-
- return 1 - np.exp(theta), theta
-
@timeout.timeout(20)
-def l1obj_l2penalization(M_val, w_val, lbda):
+def sparse_recovery(M_val, w_val, lbda):
"""
Solves:
min - sum_j theta_j + lbda*|e^{M*theta} - (1 - w)|_2
@@ -76,17 +22,25 @@ def l1obj_l2penalization(M_val, w_val, lbda):
if type(lbda) == int:
lbda = np.array(lbda)
- m, n = M_val.shape
-
theta = tensor.row().T
- z = tensor.row().T
theta_ = theta.flatten()
- z_ = z.flatten()
+
M = theano.shared(M_val.astype(theano.config.floatX))
w = theano.shared(w_val.astype(theano.config.floatX))
lbda = theano.shared(lbda.astype(theano.config.floatX))
+
y = (theta_).norm(1) + lbda * (
tensor.exp(M.dot(theta_)) - (1 - w)).norm(2)
+
+ return diff_and_opt(theta, theta_, M, w, lbda, y)
+
+
+def diff_and_opt(theta, theta_, M, w, lbda, y):
+ z = tensor.row().T
+ z_ = z.flatten()
+
+ m, n = M_val.shape
+
y_diff = tensor.grad(y, theta_)
y_hess = z[0] * theano.gradient.hessian(y, theta_)
f_x = theano.function([theta], [y, y_diff], allow_input_downcast=True)