line_energy.py 2.63 KB
 Theo Steininger committed Apr 13, 2017 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 ``````# NIFTy # Copyright (C) 2017 Theo Steininger # # Author: Theo Steininger # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . `````` Theo Steininger committed Oct 25, 2016 18 19 20 21 22 `````` from .energy import Energy class LineEnergy(Energy): `````` Jakob Knollmueller committed May 09, 2017 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 `````` """A Energy object restricting an underlying Energy along some descent direction. Given some Energy and descent direction, its position is parametrized by a scalar step size along the descent direction. Parameters ---------- position : float The step length parameter along the given line direction. Attributes ---------- position : float The step length along the given line direction. value : float The evaluation of the energy functional at given position. gradient : float The gradient along the line direction projected on the current line position. curvature : callable A positive semi-definite operator or function describing the curvature of the potential at given position. line_direction : field Direction along which the movement is restricted. Does not have to be normalized. energy : Energy The underlying Energy at the resulting position along the line according to the step length. """ `````` Theo Steininger committed Oct 25, 2016 50 `````` def __init__(self, position, energy, line_direction, zero_point=None): `````` Theo Steininger committed Oct 25, 2016 51 `````` super(LineEnergy, self).__init__(position=position) `````` Theo Steininger committed Oct 25, 2016 52 53 54 55 56 57 58 59 `````` self.line_direction = line_direction if zero_point is None: zero_point = energy.position self._zero_point = zero_point position_on_line = self._zero_point + self.position*line_direction self.energy = energy.at(position=position_on_line) `````` Theo Steininger committed Oct 25, 2016 60 61 `````` def at(self, position): `````` Theo Steininger committed Oct 25, 2016 62 63 64 65 `````` return self.__class__(position, self.energy, self.line_direction, zero_point=self._zero_point) `````` Theo Steininger committed Oct 25, 2016 66 67 68 69 70 71 72 73 74 75 76 77 `````` @property def value(self): return self.energy.value @property def gradient(self): return self.energy.gradient.dot(self.line_direction) @property def curvature(self): return self.energy.curvature``````