diff options
| -rwxr-xr-x | Wrappers/Python/ccpi/optimisation/functions/IndicatorBox.py | 119 |
1 files changed, 88 insertions, 31 deletions
diff --git a/Wrappers/Python/ccpi/optimisation/functions/IndicatorBox.py b/Wrappers/Python/ccpi/optimisation/functions/IndicatorBox.py index df8dc89..dd2162c 100755 --- a/Wrappers/Python/ccpi/optimisation/functions/IndicatorBox.py +++ b/Wrappers/Python/ccpi/optimisation/functions/IndicatorBox.py @@ -1,21 +1,25 @@ -# -*- coding: utf-8 -*- -# This work is part of the Core Imaging Library developed by -# Visual Analytics and Imaging System Group of the Science Technology -# Facilities Council, STFC +#======================================================================== +# Copyright 2019 Science Technology Facilities Council +# Copyright 2019 University of Manchester +# +# This work is part of the Core Imaging Library developed by Science Technology +# Facilities Council and University of Manchester +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0.txt +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# +#========================================================================= -# Copyright 2018-2019 Jakob Jorgensen, Daniil Kazantsev and Edoardo Pasca -# Licensed under the Apache License, Version 2.0 (the "License"); -# you may not use this file except in compliance with the License. -# You may obtain a copy of the License at - -# http://www.apache.org/licenses/LICENSE-2.0 - -# Unless required by applicable law or agreed to in writing, software -# distributed under the License is distributed on an "AS IS" BASIS, -# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -# See the License for the specific language governing permissions and -# limitations under the License. from ccpi.optimisation.functions import Function import numpy @@ -43,23 +47,76 @@ class IndicatorBox(Function): val = numpy.inf return val - def prox(self,x,tau=None): - return (x.maximum(self.lower)).minimum(self.upper) + def gradient(self,x): + return ValueError('Not Differentiable') + + def convex_conjugate(self,x): + # support function sup <x^*, x> + return 0 def proximal(self, x, tau, out=None): + if out is None: - return self.prox(x, tau) + return (x.maximum(self.lower)).minimum(self.upper) + else: + x.maximum(self.lower, out=out) + out.minimum(self.upper, out=out) + + def proximal_conjugate(self, x, tau, out=None): + + if out is None: + + return x - tau * self.proximal(x/tau, tau) + else: - if not x.shape == out.shape: - raise ValueError('Norm1 Incompatible size:', - x.shape, out.shape) - #(x.abs() - tau*self.gamma).maximum(0) * x.sign() - x.abs(out = out) - out.__isub__(tau*self.gamma) - out.maximum(0, out=out) - if self.sign_x is None or not x.shape == self.sign_x.shape: - self.sign_x = x.sign() - else: - x.sign(out=self.sign_x) + + self.proximal(x/tau, tau, out=out) + out *= -1*tau + out += x + + + +if __name__ == '__main__': + + from ccpi.framework import ImageGeometry + + N, M = 2,3 + ig = ImageGeometry(voxel_num_x = N, voxel_num_y = M) + + u = ig.allocate('random_int') + tau = 10 + + f = IndicatorBox(2, 3) + + lower = 10 + upper = 30 + + x = u + + z1 = (x.maximum(lower)).minimum(upper) + + z2 = x - tau * ((x/tau).maximum(lower)).minimum(upper) + + z = z1 + z2/tau + + print(z.array, x.array) + + +# prox = f.proximal(u, tau) +# prox_conj = f.proximal_conjugate(u/tau, tau) +# +# +# z = prox + tau * prox_conj +# print(z.as_array(), u.array) + + +# x - tau * ((x/tau).maximum(self.lower)).minimum(self.upper) + + + + + + - out.__imul__( self.sign_x ) + + + |