2 * This file is part of the GROMACS molecular simulation package.
4 * Copyright (c) 2015,2016,2017,2018,2019,2020,2021, by the GROMACS development team, led by
5 * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
6 * and including many others, as listed in the AUTHORS file in the
7 * top-level source directory and at http://www.gromacs.org.
9 * GROMACS is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public License
11 * as published by the Free Software Foundation; either version 2.1
12 * of the License, or (at your option) any later version.
14 * GROMACS is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with GROMACS; if not, see
21 * http://www.gnu.org/licenses, or write to the Free Software Foundation,
22 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
24 * If you want to redistribute modifications to GROMACS, please
25 * consider that scientific software is very special. Version
26 * control is crucial - bugs must be traceable. We will be happy to
27 * consider code for inclusion in the official distribution, but
28 * derived work must not be called official GROMACS. Details are found
29 * in the README & COPYING files - if they are missing, get the
30 * official version at http://www.gromacs.org.
32 * To help us fund GROMACS development, we humbly ask that you cite
33 * the research papers on the package. Check out http://www.gromacs.org.
39 * Declares the HistogramSize class.
41 * The data members of this class keep track of global size and update related
42 * properties of the bias histogram and the evolution of the histogram size.
43 * Initially histogramSize_ (and thus the convergence rate) is controlled
44 * heuristically to get good initial estimates, i.e. increase the robustness
47 * \author Viveca Lindahl
48 * \author Berk Hess <hess@kth.se>
52 #ifndef GMX_AWH_HISTOGRAMSIZE_H
53 #define GMX_AWH_HISTOGRAMSIZE_H
59 #include "gromacs/math/vectypes.h"
66 struct AwhBiasStateHistory;
72 * \brief Tracks global size related properties of the bias histogram.
74 * Tracks the number of updates and the histogram size.
75 * Also keep track of the stage (initial/final of the AWH method
76 * and printing warnings about covering.
78 * \note Histogram sizes are floating-point values, since the histogram uses weighted
79 * entries and we can assign a floating-point scaling factor when changing it.
84 /*! \brief Constructor.
86 * \param[in] awhBiasParams The Bias parameters from inputrec.
87 * \param[in] histogramSizeInitial The initial histogram size.
89 HistogramSize(const AwhBiasParams& awhBiasParams, double histogramSizeInitial);
93 * Returns the new size of the reference weight histogram in the initial stage.
95 * This function also takes care resetting the histogram used for covering checks
96 * and for exiting the initial stage.
98 * \param[in] params The bias parameters.
100 * \param[in] detectedCovering True if we detected that the sampling interval has been
101 * sufficiently covered. \param[in,out] weightsumCovering The weight sum for checking covering.
102 * \param[in,out] fplog Log file.
103 * \returns the new histogram size.
105 double newHistogramSizeInitialStage(const BiasParams& params,
107 bool detectedCovering,
108 ArrayRef<double> weightsumCovering,
113 * Return the new reference weight histogram size for the current update.
115 * This function also takes care of checking for covering in the initial stage.
117 * \param[in] params The bias parameters.
119 * \param[in] covered True if the sampling interval has been covered enough.
120 * \param[in] pointStates The state of the grid points.
121 * \param[in,out] weightsumCovering The weight sum for checking covering.
122 * \param[in,out] fplog Log file.
123 * \returns the new histogram size.
125 double newHistogramSize(const BiasParams& params,
128 ArrayRef<const PointState> pointStates,
129 ArrayRef<double> weightsumCovering,
132 /*! \brief Restores the histogram size from history.
134 * \param[in] stateHistory The AWH bias state history.
136 void restoreFromHistory(const AwhBiasStateHistory& stateHistory);
138 /*! \brief Store the histogram size state in a history struct.
140 * \param[in,out] stateHistory The AWH bias state history.
142 void storeState(AwhBiasStateHistory* stateHistory) const;
144 /*! \brief Returns the number of updates since the start of the simulation.
146 int numUpdates() const { return numUpdates_; }
148 /*! \brief Increments the number of updates by 1.
150 void incrementNumUpdates() { numUpdates_ += 1; }
152 /*! \brief Returns the histogram size.
154 double histogramSize() const { return histogramSize_; }
156 /*! \brief Sets the histogram size.
158 * \param[in] histogramSize The new histogram size.
159 * \param[in] weightHistogramScalingFactor The factor to scale the weight by.
161 void setHistogramSize(double histogramSize, double weightHistogramScalingFactor);
163 /*! \brief Returns true if we are in the initial stage of the AWH method.
165 bool inInitialStage() const { return inInitialStage_; }
167 /*! \brief Returns The log of the current sample weight, scaled because of the histogram rescaling.
169 double logScaledSampleWeight() const { return logScaledSampleWeight_; }
172 int64_t numUpdates_; /**< The number of updates performed since the start of the simulation. */
174 /* The histogram size sets the update size and so controls the convergence rate of the free energy and bias. */
175 double histogramSize_; /**< Size of reference weight histogram. */
177 /* Values that control the evolution of the histogram size. */
178 bool inInitialStage_; /**< True if in the intial stage. */
179 bool equilibrateHistogram_; /**< True if samples are kept from accumulating until the sampled distribution is close enough to the target. */
180 double logScaledSampleWeight_; /**< The log of the current sample weight, scaled because of the histogram rescaling. */
181 double maxLogScaledSampleWeight_; /**< Maximum sample weight obtained for previous (smaller) histogram sizes. */
183 /* Bool to avoid printing multiple, not so useful, messages to log */
184 bool havePrintedAboutCovering_; /**< True if we have printed about covering to the log while equilibrateHistogram==true */
189 #endif /* GMX_AWH_HISTOGRAMSIZE_H */