def fingerprint_relaxation(self, p0, a, k=None, ncv=None):
# basic checks for a and b
p0 = _types.ensure_ndarray(p0, ndim=1, kind='numeric')
a = _types.ensure_ndarray(a, ndim=1, kind='numeric', size=len(p0))
# are we on microstates space?
if len(a) == self.nstates_obs:
p0 = _np.dot(self.observation_probabilities, p0)
a = _np.dot(self.observation_probabilities, a)
# now we are on macrostate space, or something is wrong
if len(a) == self.nstates:
return _MSM.fingerprint_relaxation(self, p0, a)
else:
raise ValueError(
'observable vectors have size %s which is incompatible with both hidden (%s)'
' and observed states (%s)' %
(len(a), self.nstates, self.nstates_obs))
def expectation(self, a):
r"""Equilibrium expectation value of a given observable.
Parameters
----------
a : (n,) ndarray
Observable vector on the MSM state space
Returns
-------
val: float
Equilibrium expectation value fo the given observable
Notes
-----
The equilibrium expectation value of an observable :math:`a` is defined as follows
.. math::
\mathbb{E}_{\mu}[a] = \sum_i \pi_i a_i
:math:`\pi=(\pi_i)` is the stationary vector of the transition matrix :math:`P`.
"""
# check input and go
a = _types.ensure_ndarray(a, ndim=1, size=self.nstates, kind='numeric')
return _np.dot(a, self.stationary_distribution)
def test_estimator(self, test_estimator):
self._test_estimator = test_estimator
self.active_set = types.ensure_ndarray(np.array(
test_estimator.active_set),
kind='i') # create a copy
# map from the full set (here defined by the largest state index in active set) to active
self._full2active = np.zeros(np.max(self.active_set) + 1, dtype=int)
self._full2active[self.active_set] = np.arange(self.nstates)
def __init__(self,
test_model,
test_estimator,
mlags=None,
conf=0.95,
err_est=False,
n_jobs=None,
show_progress=True):
# set model and estimator
# copy the test model, since the estimation of cktest modifies the model.
from copy import deepcopy
self.test_model = deepcopy(test_model)
self.test_estimator = test_estimator
# set mlags
try:
maxlength = np.max([
len(dtraj)
for dtraj in test_estimator.discrete_trajectories_full
])
except AttributeError:
maxlength = np.max(test_estimator.trajectory_lengths())
maxmlag = int(math.floor(maxlength / test_estimator.lag))
if mlags is None:
mlags = maxmlag
if types.is_int(mlags):
mlags = np.arange(mlags)
mlags = types.ensure_ndarray(mlags, ndim=1, kind='i')
if np.any(mlags > maxmlag):
mlags = mlags[np.where(mlags <= maxmlag)]
self.logger.warning(
'Changed mlags as some mlags exceeded maximum trajectory length.'
)
if np.any(mlags < 0):
mlags = mlags[np.where(mlags >= 0)]
self.logger.warning('Changed mlags as some mlags were negative.')
self.mlags = mlags
# set conf and error handling
self.conf = conf
self.has_errors = issubclass(self.test_model.__class__, SampledModel)
if self.has_errors:
self.test_model.set_model_params(conf=conf)
self.err_est = err_est
if err_est and not self.has_errors:
raise ValueError(
'Requested errors on the estimated models, '
'but the model is not able to calculate errors at all')
self.n_jobs = n_jobs
self.show_progress = show_progress
def propagate(self, p0, k):
r""" Propagates the initial distribution p0 k times
Computes the product
.. math::
p_k = p_0^T P^k
If the lag time of transition matrix :math:`P` is :math:`\tau`, this
will provide the probability distribution at time :math:`k \tau`.
Parameters
----------
p0 : ndarray(n)
Initial distribution. Vector of size of the active set.
k : int
Number of time steps
Returns
----------
pk : ndarray(n)
Distribution after k steps. Vector of size of the active set.
"""
p0 = _types.ensure_ndarray(p0, ndim=1, kind='numeric')
assert _types.is_int(k) and k >= 0, 'k must be a non-negative integer'
if k == 0: # simply return p0 normalized
return p0 / p0.sum()
micro = False
# are we on microstates space?
if len(p0) == self.nstates_obs:
micro = True
# project to hidden and compute
p0 = _np.dot(self.observation_probabilities, p0)
self._ensure_eigendecomposition(self.nstates)
from pyerna.util.linalg import mdot
pk = mdot(p0.T, self.eigenvectors_right(),
_np.diag(_np.power(self.eigenvalues(), k)),
self.eigenvectors_left())
if micro:
pk = _np.dot(pk, self.observation_probabilities
) # convert back to microstate space
# normalize to 1.0 and return
return pk / pk.sum()
def propagate(self, p0, k):
r""" Propagates the initial distribution p0 k times
Computes the product
.. math::
p_k = p_0^T P^k
If the lag time of transition matrix :math:`P` is :math:`\tau`, this
will provide the probability distribution at time :math:`k \tau`.
Parameters
----------
p0 : ndarray(n,)
Initial distribution. Vector of size of the active set.
k : int
Number of time steps
Returns
----------
pk : ndarray(n,)
Distribution after k steps. Vector of size of the active set.
"""
p0 = _types.ensure_ndarray(p0, ndim=1, size=self.nstates, kind='numeric')
assert _types.is_int(k) and k >= 0, 'k must be a non-negative integer'
if k == 0: # simply return p0 normalized
return p0 / p0.sum()
if self.is_sparse: # sparse: we don't have a full eigenvalue set, so just propagate
pk = _np.array(p0)
for i in range(k):
pk = _np.dot(pk.T, self.transition_matrix)
else: # dense: employ eigenvalue decomposition
self._ensure_eigendecomposition(self.nstates)
from pyerna.util.linalg import mdot
pk = mdot(p0.T,
self.eigenvectors_right(),
_np.diag(_np.power(self.eigenvalues(), k)),
self.eigenvectors_left()).real
# normalize to 1.0 and return
return pk / pk.sum()
def correlation(self, a, b=None, maxtime=None, k=None, ncv=None):
# basic checks for a and b
a = _types.ensure_ndarray(a, ndim=1, kind='numeric')
b = _types.ensure_ndarray_or_None(b,
ndim=1,
kind='numeric',
size=len(a))
# are we on microstates space?
if len(a) == self.nstates_obs:
a = _np.dot(self.observation_probabilities, a)
if b is not None:
b = _np.dot(self.observation_probabilities, b)
# now we are on macrostate space, or something is wrong
if len(a) == self.nstates:
return _MSM.correlation(self, a, b=b, maxtime=maxtime)
else:
raise ValueError(
'observable vectors have size %s which is incompatible with both hidden (%s)'
' and observed states (%s)' %
(len(a), self.nstates, self.nstates_obs))
def plot_network(self,
state_sizes=None,
state_scale=1.0,
state_colors='#ff5500',
state_labels='auto',
arrow_scale=1.0,
arrow_curvature=1.0,
arrow_labels='weights',
arrow_label_format='%10.2f',
max_width=12,
max_height=12,
figpadding=0.2,
xticks=False,
yticks=False,
show_frame=False,
**textkwargs):
"""
Draws a network using discs and curved arrows.
The thicknesses and labels of the arrows are taken from the off-diagonal matrix elements
in A.
"""
# Set the default values for the text dictionary
from matplotlib import pyplot as _plt
textkwargs.setdefault('size', None)
textkwargs.setdefault('horizontalalignment', 'center')
textkwargs.setdefault('verticalalignment', 'center')
textkwargs.setdefault('color', 'black')
# remove the temporary key 'arrow_label_size' as it cannot be parsed by plt.text!
arrow_label_size = textkwargs.pop('arrow_label_size',
textkwargs['size'])
if self.pos is None:
self.layout_automatic()
# number of nodes
n = len(self.pos)
# get bounds and pad figure
xmin = _np.min(self.pos[:, 0])
xmax = _np.max(self.pos[:, 0])
Dx = xmax - xmin
xmin -= Dx * figpadding
xmax += Dx * figpadding
Dx *= 1 + figpadding
ymin = _np.min(self.pos[:, 1])
ymax = _np.max(self.pos[:, 1])
Dy = ymax - ymin
ymin -= Dy * figpadding
ymax += Dy * figpadding
Dy *= 1 + figpadding
# sizes of nodes
if state_sizes is None:
state_sizes = 0.5 * state_scale * \
min(Dx, Dy)**2 * _np.ones(n) / float(n)
else:
state_sizes = 0.5 * state_scale * \
min(Dx, Dy)**2 * state_sizes / (_np.max(state_sizes) * float(n))
# automatic arrow rescaling
arrow_scale *= 1.0 / \
(_np.max(self.A - _np.diag(_np.diag(self.A))) * _sqrt(n))
# size figure
if (Dx / max_width > Dy / max_height):
figsize = (max_width, Dy * (max_width / Dx))
else:
figsize = (Dx / Dy * max_height, max_height)
if self.ax is None:
logger.debug("creating new figure")
fig = _plt.figure(None, figsize=figsize)
self.ax = fig.add_subplot(111)
else:
fig = self.ax.figure
window_extend = self.ax.get_window_extent()
axes_ratio = window_extend.height / window_extend.width
data_ratio = (ymax - ymin) / (xmax - xmin)
q = axes_ratio / data_ratio
if q > 1.0:
ymin *= q
ymax *= q
else:
xmin /= q
xmax /= q
if not xticks:
self.ax.get_xaxis().set_ticks([])
if not yticks:
self.ax.get_yaxis().set_ticks([])
# show or suppress frame
self.ax.set_frame_on(show_frame)
# set node labels
if state_labels is None:
pass
elif isinstance(state_labels, str) and state_labels == 'auto':
state_labels = [str(i) for i in _np.arange(n)]
else:
if len(state_labels) != n:
raise ValueError(
"length of state_labels({}) has to match length of states({})."
.format(len(state_labels), n))
# set node colors
if state_colors is None:
state_colors = '#ff5500' # None is not acceptable
if isinstance(state_colors, str):
state_colors = [state_colors] * n
if isinstance(state_colors, list) and not len(state_colors) == n:
raise ValueError(
"Mistmatch between nstates and nr. state_colors (%u vs %u)" %
(n, len(state_colors)))
try:
colorscales = _types.ensure_ndarray(state_colors,
ndim=1,
kind='numeric')
colorscales /= colorscales.max()
state_colors = [
_plt.cm.binary(int(256.0 * colorscales[i])) for i in range(n)
]
except AssertionError:
# assume we have a list of strings now.
logger.debug("could not cast 'state_colors' to numeric values.")
# set arrow labels
if isinstance(arrow_labels, _np.ndarray):
L = arrow_labels
if isinstance(arrow_labels[0, 0], str):
arrow_label_format = '%s'
elif isinstance(arrow_labels,
str) and arrow_labels.lower() == 'weights':
L = self.A[:, :]
elif arrow_labels is None:
L = _np.empty(_np.shape(self.A), dtype=object)
L[:, :] = ''
arrow_label_format = '%s'
else:
raise ValueError('invalid arrow labels')
# draw circles
circles = []
for i in range(n):
# choose color
c = _plt.Circle(self.pos[i],
radius=_sqrt(0.5 * state_sizes[i]) / 2.0,
color=state_colors[i],
zorder=2)
circles.append(c)
self.ax.add_artist(c)
# add annotation
if state_labels is not None:
self.ax.text(self.pos[i][0],
self.pos[i][1],
state_labels[i],
zorder=3,
**textkwargs)
assert len(circles) == n, "%i != %i" % (len(circles), n)
# draw arrows
for i in range(n):
for j in range(i + 1, n):
if (abs(self.A[i, j]) > 0):
self._draw_arrow(self.pos[i, 0],
self.pos[i, 1],
self.pos[j, 0],
self.pos[j, 1],
Dx,
Dy,
label=arrow_label_format % L[i, j],
width=arrow_scale * self.A[i, j],
arrow_curvature=arrow_curvature,
patchA=circles[i],
patchB=circles[j],
shrinkA=3,
shrinkB=0,
arrow_label_size=arrow_label_size)
if (abs(self.A[j, i]) > 0):
self._draw_arrow(self.pos[j, 0],
self.pos[j, 1],
self.pos[i, 0],
self.pos[i, 1],
Dx,
Dy,
label=arrow_label_format % L[j, i],
width=arrow_scale * self.A[j, i],
arrow_curvature=arrow_curvature,
patchA=circles[j],
patchB=circles[i],
shrinkA=3,
shrinkB=0,
arrow_label_size=arrow_label_size)
# plot
self.ax.set_xlim(xmin, xmax)
self.ax.set_ylim(ymin, ymax)
return fig
def cktest(self,
n_observables=None,
observables='phi',
statistics='psi',
mlags=10,
n_jobs=None,
show_progress=True,
iterable=None):
r"""Do the Chapman-Kolmogorov test by computing predictions for higher lag times and by performing estimations at higher lag times.
Notes
-----
This method computes two sets of time-lagged covariance matrices
* estimates at higher lag times :
.. math::
\left\langle \mathbf{K}(n\tau)g_{i},f_{j}\right\rangle_{\rho_{0}}
where :math:`\rho_{0}` is the empirical distribution implicitly defined
by all data points from time steps 0 to T-tau in all trajectories,
:math:`\mathbf{K}(n\tau)` is a rank-reduced Koopman matrix estimated
at the lag-time n*tau and g and f are some functions of the data.
Rank-reduction of the Koopman matrix is controlled by the `dim`
parameter of :func:`vamp <pyerna.coordinates.vamp>`.
* predictions at higher lag times :
.. math::
\left\langle \mathbf{K}^{n}(\tau)g_{i},f_{j}\right\rangle_{\rho_{0}}
where :math:`\mathbf{K}^{n}` is the n'th power of the rank-reduced
Koopman matrix contained in self.
The Champan-Kolmogorov test is to compare the predictions to the
estimates.
Parameters
----------
n_observables : int, optional, default=None
Limit the number of default observables (and of default statistics)
to this number.
Only used if `observables` are None or `statistics` are None.
observables : np.ndarray((input_dimension, n_observables)) or 'phi'
Coefficients that express one or multiple observables :math:`g`
in the basis of the input features.
This parameter can be 'phi'. In that case, the dominant
right singular functions of the Koopman operator estimated
at the smallest lag time are used as default observables.
statistics : np.ndarray((input_dimension, n_statistics)) or 'psi'
Coefficients that express one or multiple statistics :math:`f`
in the basis of the input features.
This parameter can be 'psi'. In that case, the dominant
left singular functions of the Koopman operator estimated
at the smallest lag time are used as default statistics.
mlags : int or int-array, default=10
multiples of lag times for testing the Model, e.g. range(10).
A single int will trigger a range, i.e. mlags=10 maps to
mlags=range(10).
Note that you need to be able to do a model prediction for each
of these lag time multiples, e.g. the value 0 only make sense
if model.expectation(lag_multiple=0) will work.
n_jobs : int, default=None
how many jobs to use during calculation
show_progress : bool, default=True
Show progressbars for calculation?
iterable : any data format that `pyerna.coordinates.vamp()` accepts as input, optional
It `iterable` is None, the same data source with which VAMP
was initialized will be used for all estimation.
Otherwise, all estimates (not predictions) from data will be computed
from the data contained in `iterable`.
Returns
-------
vckv : :class:`VAMPChapmanKolmogorovValidator <pyerna.coordinates.transform.VAMPChapmanKolmogorovValidator>`
Contains the estimated and the predicted covarince matrices.
The object can be plotted with :func:`plot_cktest <pyerna.plots.plot_cktest>` with the option `y01=False`.
"""
if n_observables is not None:
if n_observables > self.dimension():
warnings.warn(
'Selected singular functions as observables but dimension '
'is lower than requested number of observables.')
n_observables = self.dimension()
else:
n_observables = self.dimension()
if isinstance(observables, str) and observables == 'phi':
observables = self.singular_vectors_right[:, 0:n_observables]
observables_mean_free = True
else:
ensure_ndarray(observables, ndim=2)
observables_mean_free = False
if isinstance(statistics, str) and statistics == 'psi':
statistics = self.singular_vectors_left[:, 0:n_observables]
statistics_mean_free = True
else:
ensure_ndarray_or_None(statistics, ndim=2)
statistics_mean_free = False
ck = VAMPChapmanKolmogorovValidator(self.model,
self,
observables,
statistics,
observables_mean_free,
statistics_mean_free,
mlags=mlags,
n_jobs=n_jobs,
show_progress=show_progress)
if iterable is None:
iterable = self.data_producer
ck.estimate(iterable)
return ck
def __init__(self,
bias_energies_full,
lag,
count_mode='sliding',
connectivity='reversible_pathways',
maxiter=10000,
maxerr=1.0E-15,
save_convergence_info=0,
dt_traj='1 step',
init=None,
init_maxiter=10000,
init_maxerr=1.0E-8):
r""" Discrete Transition(-based) Reweighting Analysis Method
Parameters
----------
bias_energies_full : numpy.ndarray(shape=(num_therm_states, num_conf_states)) object
bias_energies_full[j, i] is the bias energy in units of kT for each discrete state i
at thermodynamic state j.
lag : int
Integer lag time at which transitions are counted.
count_mode : str, optional, default='sliding'
Mode to obtain count matrices from discrete trajectories. Should be one of:
* 'sliding' : a trajectory of length T will have :math:`T-\tau` counts at time indexes
.. math::
(0 \rightarrow \tau), (1 \rightarrow \tau+1), ..., (T-\tau-1 \rightarrow T-1)
* 'sample' : a trajectory of length T will have :math:`T/\tau` counts at time indexes
.. math::
(0 \rightarrow \tau), (\tau \rightarrow 2 \tau), ..., ((T/\tau-1) \tau \rightarrow T)
Currently only 'sliding' is supported.
connectivity : str, optional, default='reversible_pathways'
One of 'reversible_pathways', 'summed_count_matrix' or None.
Defines what should be considered a connected set in the joint (product)
space of conformations and thermodynamic ensembles.
* 'reversible_pathways' : requires that every state in the connected set
can be reached by following a pathway of reversible transitions. A
reversible transition between two Markov states (within the same
thermodynamic state k) is a pair of Markov states that belong to the
same strongly connected component of the count matrix (from
thermodynamic state k). A pathway of reversible transitions is a list of
reversible transitions [(i_1, i_2), (i_2, i_3),..., (i_(N-2), i_(N-1)),
(i_(N-1), i_N)]. The thermodynamic state where the reversible
transitions happen, is ignored in constructing the reversible pathways.
This is equivalent to assuming that two ensembles overlap at some Markov
state whenever there exist frames from both ensembles in that Markov
state.
* 'summed_count_matrix' : all thermodynamic states are assumed to overlap.
The connected set is then computed by summing the count matrices over
all thermodynamic states and taking it's largest strongly connected set.
Not recommended!
* None : assume that everything is connected. For debugging.
For more details see :func:`pyerna.thermo.extensions.cset.compute_csets_dTRAM`.
maxiter : int, optional, default=10000
The maximum number of self-consistent iterations before the estimator exits unsuccessfully.
maxerr : float, optional, default=1.0E-15
Convergence criterion based on the maximal free energy change in a self-consistent
iteration step.
save_convergence_info : int, optional, default=0
Every save_convergence_info iteration steps, store the actual increment
and the actual log-likelihood; 0 means no storage.
dt_traj : str, optional, default='1 step'
Description of the physical time corresponding to the lag. May be used by analysis
algorithms such as plotting tools to pretty-print the axes. By default '1 step', i.e.
there is no physical time unit. Specify by a number, whitespace and unit. Permitted
units are (* is an arbitrary string):
| 'fs', 'femtosecond*'
| 'ps', 'picosecond*'
| 'ns', 'nanosecond*'
| 'us', 'microsecond*'
| 'ms', 'millisecond*'
| 's', 'second*'
init : str, optional, default=None
Use a specific initialization for self-consistent iteration:
| None: use a hard-coded guess for free energies and Lagrangian multipliers
| 'wham': perform a short WHAM estimate to initialize the free energies
init_maxiter : int, optional, default=10000
The maximum number of self-consistent iterations during the initialization.
init_maxerr : float, optional, default=1.0E-8
Convergence criterion for the initialization.
Example
-------
>>> from pyerna.thermo import DTRAM
>>> import numpy as np
>>> B = np.array([[0, 0],[0.5, 1.0]])
>>> dtram = DTRAM(B, 1)
>>> ttrajs = [np.array([0,0,0,0,0,0,0,0,0,0]),np.array([1,1,1,1,1,1,1,1,1,1])]
>>> dtrajs = [np.array([0,0,0,0,1,1,1,0,0,0]),np.array([0,1,0,1,0,1,1,0,0,1])]
>>> dtram = dtram.estimate((ttrajs, dtrajs))
>>> dtram.log_likelihood() # doctest: +ELLIPSIS
-9.805...
>>> dtram.count_matrices # doctest: +SKIP
array([[[5, 1],
[1, 2]],
[[1, 4],
[3, 1]]], dtype=int32)
>>> dtram.stationary_distribution # doctest: +ELLIPSIS
array([ 0.38..., 0.61...])
>>> dtram.meval('stationary_distribution') # doctest: +ELLIPSIS
[array([ 0.38..., 0.61...]), array([ 0.50..., 0.49...])]
References
----------
.. [1] Wu, H. et al 2014
Statistically optimal analysis of state-discretized trajectory data from multiple thermodynamic states
J. Chem. Phys. 141, 214106
"""
# set all parameters
self.bias_energies_full = _types.ensure_ndarray(bias_energies_full,
ndim=2,
kind='numeric')
self.lag = lag
assert count_mode == 'sliding', 'Currently the only implemented count_mode is \'sliding\''
self.count_mode = count_mode
assert connectivity in [ None, 'reversible_pathways', 'summed_count_matrix' ], \
'Currently the only implemented connectivity checks are \'reversible_pathways\', \'summed_count_matrix\' and None'
self.connectivity = connectivity
self.dt_traj = dt_traj
self.maxiter = maxiter
self.maxerr = maxerr
self.save_convergence_info = save_convergence_info
assert init in (
None, 'wham'), 'Currently only None and \'wham\' are supported'
self.init = init
self.init_maxiter = init_maxiter
self.init_maxerr = init_maxerr
# set derived quantities
self.nthermo, self.nstates_full = bias_energies_full.shape
# set iteration variables
self.therm_energies = None
self.conf_energies = None
self.log_lagrangian_mult = None
def __init__(self,
bias_energies_full,
maxiter=10000,
maxerr=1.0E-15,
save_convergence_info=0,
dt_traj='1 step',
stride=1):
r"""Weighted Histogram Analysis Method
Parameters
----------
bias_energies_full : numpy.ndarray(shape=(num_therm_states, num_conf_states)) object
bias_energies_full[j, i] is the bias energy in units of kT for each discrete state i
at thermodynamic state j.
maxiter : int, optional, default=10000
The maximum number of self-consistent iterations before the estimator exits unsuccessfully.
maxerr : float, optional, default=1.0E-15
Convergence criterion based on the maximal free energy change in a self-consistent
iteration step.
save_convergence_info : int, optional, default=0
Every save_convergence_info iteration steps, store the actual increment
and the actual loglikelihood; 0 means no storage.
dt_traj : str, optional, default='1 step'
Description of the physical time corresponding to the lag. May be used by analysis
algorithms such as plotting tools to pretty-print the axes. By default '1 step', i.e.
there is no physical time unit. Specify by a number, whitespace and unit. Permitted
units are (* is an arbitrary string):
| 'fs', 'femtosecond*'
| 'ps', 'picosecond*'
| 'ns', 'nanosecond*'
| 'us', 'microsecond*'
| 'ms', 'millisecond*'
| 's', 'second*'
stride : int, optional, default=1
not used
Example
-------
>>> from pyerna.thermo import WHAM
>>> import numpy as np
>>> B = np.array([[0, 0],[0.5, 1.0]])
>>> wham = WHAM(B)
>>> ttrajs = [np.array([0,0,0,0,0,0,0,0,0,0]),np.array([1,1,1,1,1,1,1,1,1,1])]
>>> dtrajs = [np.array([0,0,0,0,1,1,1,0,0,0]),np.array([0,1,0,1,0,1,1,0,0,1])]
>>> wham = wham.estimate((ttrajs, dtrajs))
>>> wham.log_likelihood() # doctest: +ELLIPSIS
-6.6...
>>> wham.state_counts # doctest: +SKIP
array([[7, 3],
[5, 5]])
>>> wham.stationary_distribution # doctest: +ELLIPSIS +REPORT_NDIFF
array([ 0.5..., 0.4...])
>>> wham.meval('stationary_distribution') # doctest: +ELLIPSIS +REPORT_NDIFF
[array([ 0.5..., 0.4...]), array([ 0.6..., 0.3...])]
References
----------
.. [1] Ferrenberg, A.M. and Swensen, R.H. 1988.
New Monte Carlo Technique for Studying Phase Transitions.
Phys. Rev. Lett. 23, 2635--2638
.. [2] Kumar, S. et al 1992.
The Weighted Histogram Analysis Method for Free-Energy Calculations on Biomolecules. I. The Method.
J. Comp. Chem. 13, 1011--1021
"""
self.bias_energies_full = _types.ensure_ndarray(bias_energies_full,
ndim=2,
kind='numeric')
self.stride = stride
self.dt_traj = dt_traj
self.maxiter = maxiter
self.maxerr = maxerr
self.save_convergence_info = save_convergence_info
# set derived quantities
self.nthermo, self.nstates_full = bias_energies_full.shape
# set iteration variables
self.therm_energies = None
self.conf_energies = None
def memberships(self, value):
self._memberships = types.ensure_ndarray(value, ndim=2, kind='numeric')
self.nstates, self.nsets = self._memberships.shape
assert np.allclose(self._memberships.sum(axis=1),
np.ones(self.nstates)) # stochastic matrix?
