def init_first(self):
# update the shape if select is present
if self.select is not None:
self.shape = (len(self.select), ) + self.shape[1:]
# compute the number of dimensions, i.e. 3 for atoms
self.ndim = 1
for s in self.shape[1:]:
self.ndim *= s
# allocate working arrays
self.last_poss = [
np.zeros(self.shape, float) for i in range(self.mult)
]
self.pos = np.zeros(self.shape, float)
# prepare the hdf5 output file, if present.
AnalysisHook.init_first(self)
if self.outg is not None:
for m in range(self.mult):
self.outg.create_dataset('msd%03i' % (m + 1),
shape=(0, ),
maxshape=(None, ),
dtype=float)
self.outg.create_dataset('msdsums', data=self.msdsums)
self.outg.create_dataset('msdcounters', data=self.msdcounters)
self.outg.create_dataset('pars', shape=(2, ), dtype=float)
self.outg.create_dataset('pars_error', shape=(2, ), dtype=float)
def init_first(self):
AnalysisHook.init_first(self)
if self.outg is not None:
self.outg.create_dataset('amps', (self.ssize,), float)
self.outg.create_dataset('freqs', (self.ssize,), float)
self.outg.create_dataset('ac', (self.ssize,), float)
self.outg.create_dataset('time', (self.ssize,), float)
def init_first(self):
AnalysisHook.init_first(self)
if self.outg is not None:
self.outg.create_dataset("amps", (self.ssize,), float)
self.outg.create_dataset("freqs", (self.ssize,), float)
self.outg.create_dataset("ac", (self.ssize,), float)
self.outg.create_dataset("time", (self.ssize,), float)
def init_first(self):
'''Setup some work arrays'''
# determine the number of atoms
if self.select0 is None:
self.natom0 = self.natom
else:
self.natom0 = len(self.select0)
self.pos0 = np.zeros((self.natom0, 3), float)
# the number of pairs
if self.select1 is None:
self.npair = (self.natom0 * (self.natom0 - 1)) // 2
self.pos1 = None
else:
self.natom1 = len(self.select1)
self.pos1 = np.zeros((self.natom1, 3), float)
self.npair = self.natom0 * self.natom1
# multiply the number of pairs by all images
self.npair *= (1 + 2 * self.nimage)**3
# Prepare the output
self.work = np.zeros(self.npair, float)
AnalysisHook.init_first(self)
if self.outg is not None:
self.outg.create_dataset('rdf', (self.nbin, ), float)
self.outg.create_dataset('CN', (self.nbin, ), float)
self.outg['d'] = self.d
if self.pairs_sr is not None:
self.outg.create_dataset('rdf_sr', (self.nbin, ), float)
def init_first(self):
AnalysisHook.init_first(self)
if self.outg is not None:
self.outg.create_dataset('amps', (self.ssize, ), float)
self.outg.create_dataset('freqs', (self.ssize, ), float)
self.outg.create_dataset('ac', (self.ssize, ), float)
self.outg.create_dataset('time', (self.ssize, ), float)
def init_first(self):
'''Setup some work arrays'''
# determine the number of atoms
if self.select0 is None:
self.natom0 = self.natom
else:
self.natom0 = len(self.select0)
self.pos0 = np.zeros((self.natom0, 3), float)
# the number of pairs
if self.select1 is None:
self.npair = (self.natom0*(self.natom0-1))/2
self.pos1 = None
else:
self.natom1 = len(self.select1)
self.pos1 = np.zeros((self.natom1, 3), float)
self.npair = self.natom0*self.natom1
# multiply the number of pairs by all images
self.npair *= (1 + 2*self.nimage)**3
# Prepare the output
self.work = np.zeros(self.npair, float)
AnalysisHook.init_first(self)
if self.outg is not None:
self.outg.create_dataset('rdf', (self.nbin,), float)
self.outg['d'] = self.d
if self.pairs_sr is not None:
self.outg.create_dataset('rdf_sr', (self.nbin,), float)
def __init__(self, f=None, start=0, end=-1, step=1, mult=20, select=None,
bsize=None, pospath='trajectory/pos', poskey='pos', outpath=None):
"""Computes mean-squared displacements and diffusion constants
**Optional arguments:**
f
An h5.File instance containing the trajectory data. If ``f``
is not given, or it does not contain the dataset referred to
with the ``path`` argument, an on-line analysis is carried out.
start, end, step
Optional arguments for the ``get_slice`` function. max_sample is
not supported because the choice of the step argument is
critical for a useful result.
mult
In the first place, the mean square displacement (MSD) between
subsequent step is computed. The MSD is also computed between
every, two, three, ..., until ``mult`` steps.
select
A list of atom indexes that are considered for the computation
of the MSD's. If not given, all atoms are used.
bsize
If given, time intervals that coincide with the boundaries of
the block size, will not be considered form the analysis. This
is useful when there is a significant monte carlo move between
subsequent blocks. If step > 1, the intervals will be left out
if the overlap with boundaries of blocks with size bsize*step.
pospath
The path of the dataset that contains the time dependent data in
the HDF5 file. The first axis of the array must be the time
axis.
poskey
In case of an on-line analysis, this is the key of the state
item that contains the data from which the MSD's are derived.
outpath
The output path for the MSD results. If not given, it defaults
to '%s_diff' % path. If this path already exists, it will be
removed first.
"""
if bsize is not None and bsize < mult:
raise ValueError('The bsize parameter must be larger than mult.')
self.mult = mult
self.select = select
self.bsize = bsize
self.msdsums = np.zeros(self.mult, float)
self.msdcounters = np.zeros(self.mult, int)
self.counter = 0
if outpath is None:
outpath = pospath + '_diff'
analysis_inputs = {'pos': AnalysisInput(pospath, poskey)}
AnalysisHook.__init__(self, f, start, end, None, step, analysis_inputs, outpath, True)
def init_first(self):
# update the shape if select is present
if self.select is not None:
self.shape = (len(self.select),) + self.shape[1:]
# compute the number of dimensions, i.e. 3 for atoms
self.ndim = 1
for s in self.shape[1:]:
self.ndim *= s
# allocate working arrays
self.last_poss = [np.zeros(self.shape, float) for i in range(self.mult)]
self.pos = np.zeros(self.shape, float)
# prepare the hdf5 output file, if present.
AnalysisHook.init_first(self)
if self.outg is not None:
for m in range(self.mult):
self.outg.create_dataset('msd%03i' % (m+1), shape=(0,), maxshape=(None,), dtype=float)
self.outg.create_dataset('msdsums', data=self.msdsums)
self.outg.create_dataset('msdcounters', data=self.msdcounters)
self.outg.create_dataset('pars', shape=(2,), dtype=float)
self.outg.create_dataset('pars_error', shape=(2,), dtype=float)
def __init__(self,
f=None,
start=0,
end=-1,
step=1,
mult=20,
select=None,
bsize=None,
pospath='trajectory/pos',
poskey='pos',
outpath=None):
"""Computes mean-squared displacements and diffusion constants
**Optional arguments:**
f
An h5.File instance containing the trajectory data. If ``f``
is not given, or it does not contain the dataset referred to
with the ``path`` argument, an on-line analysis is carried out.
start, end, step
Optional arguments for the ``get_slice`` function. max_sample is
not supported because the choice of the step argument is
critical for a useful result.
mult
In the first place, the mean square displacement (MSD) between
subsequent step is computed. The MSD is also computed between
every, two, three, ..., until ``mult`` steps.
select
A list of atom indexes that are considered for the computation
of the MSD's. If not given, all atoms are used.
bsize
If given, time intervals that coincide with the boundaries of
the block size, will not be considered form the analysis. This
is useful when there is a significant monte carlo move between
subsequent blocks. If step > 1, the intervals will be left out
if the overlap with boundaries of blocks with size bsize*step.
pospath
The path of the dataset that contains the time dependent data in
the HDF5 file. The first axis of the array must be the time
axis.
poskey
In case of an on-line analysis, this is the key of the state
item that contains the data from which the MSD's are derived.
outpath
The output path for the MSD results. If not given, it defaults
to '%s_diff' % path. If this path already exists, it will be
removed first.
"""
if bsize is not None and bsize < mult:
raise ValueError('The bsize parameter must be larger than mult.')
self.mult = mult
self.select = select
self.bsize = bsize
self.msdsums = np.zeros(self.mult, float)
self.msdcounters = np.zeros(self.mult, int)
self.counter = 0
if outpath is None:
outpath = pospath + '_diff'
analysis_inputs = {'pos': AnalysisInput(pospath, poskey)}
AnalysisHook.__init__(self, f, start, end, None, step, analysis_inputs,
outpath, True)
def __init__(self, f=None, start=0, end=-1, step=1, bsize=4096, select=None,
path='trajectory/vel', key='vel', outpath=None, weights=None):
"""
**Optional arguments:**
f
An h5.File instance containing the trajectory data. If ``f``
is not given, or it does not contain the dataset referred to
with the ``path`` argument, an on-line analysis is carried out.
start
The first sample to be considered for analysis. This may be
negative to indicate that the analysis should start from the
-start last samples.
end
The last sample to be considered for analysis. This may be
negative to indicate that the last -end sample should not be
considered.
step
The spacing between the samples used for the analysis
bsize
The size of the blocks used for individual FFT calls.
select
A list of atom indexes that are considered for the computation
of the spectrum. If not given, all atoms are used.
path
The path of the dataset that contains the time dependent data in
the HDF5 file. The first axis of the array must be the time
axis. The spectra are summed over the other axes.
key
In case of an on-line analysis, this is the key of the state
item that contains the data from which the spectrum is derived.
outpath
The output path for the frequency computation in the HDF5 file.
If not given, it defaults to '%s_spectrum' % path. If this path
already exists, it will be removed first.
weights
If not given, the spectrum is just a simple sum of contributions
from different time-dependent functions. If given, a linear
combination is made based on these weights.
The max_sample argument from get_slice is not used because the choice
step value is an important parameter: it is best to choose step*bsize
such that it coincides with a part of the trajectory in which the
velocities (or other data) are continuous.
The block size should be set such that it corresponds to a decent
resolution on the frequency axis, i.e. 33356 fs of MD data
corresponds to a resolution of about 1 cm^-1. The step size should be
set such that the highest frequency is above the highest relevant
frequency in the spectrum, e.g. a step of 10 fs corresponds to a
frequency maximum of 3336 cm^-1. The total number of FFT's, i.e.
length of the simulation divided by the block size multiplied by the
number of time-dependent functions in the data, determines the noise
reduction on the (the amplitude of) spectrum. If there is sufficient
data to perform 10K FFT's, one should get a reasonably smooth
spectrum.
Depending on the FFT implementation in numpy, it may be interesting
to tune the bsize argument. A power of 2 is typically a good choice.
When f is None, or when the path does not exist in the HDF5 file, the
class can be used as an on-line analysis hook for the iterative
algorithms in yaff.sampling package. This means that the spectrum
is built up as the iterative algorithm progresses. The end option is
ignored for an on-line analysis.
"""
self.bsize = bsize
self.select = select
self.weights = weights
self.ssize = self.bsize//2+1 # the length of the spectrum array
self.amps = np.zeros(self.ssize, float)
self.nfft = 0 # the number of fft calls, for statistics
if outpath is None:
outpath = path + '_spectrum'
analysis_inputs = {'signal': AnalysisInput(path, key)}
AnalysisHook.__init__(self, f, start, end, None, step, analysis_inputs, outpath, True)
def init_online(self):
AnalysisHook.init_online(self)
self.ncollect = 0
def __init__(self,
rcut,
rspacing,
f=None,
start=0,
end=-1,
max_sample=None,
step=None,
select0=None,
select1=None,
pairs_sr=None,
nimage=0,
pospath='trajectory/pos',
poskey='pos',
cellpath=None,
cellkey=None,
outpath=None):
"""Computes a radial distribution function (RDF)
**Argument:**
rcut
The cutoff for the RDF analysis. This should be lower than the
spacing between the primitive cell planes, multiplied by (1+2*nimage).
rspacing
The width of the bins to build up the RDF.
**Optional arguments:**
f
An h5.File instance containing the trajectory data. If ``f``
is not given, or it does not contain the dataset referred to
with the ``path`` argument, an on-line analysis is carried out.
start, end, max_sample, step
arguments to setup the selection of time slices. See
``get_slice`` for more information.
select0
A list of atom indexes that are considered for the computation
of the rdf. If not given, all atoms are used.
select1
A list of atom indexes that are needed to compute an RDF between
two disjoint sets of atoms. (If there is some overlap between
select0 and select1, an error will be raised.) If this is None,
an 'internal' RDF will be computed for the atoms specified in
select0.
pairs_sr
An array with short-range pairs of atoms (shape K x 2). When
given, an additional RDFs is generated for the short-range pairs
(rdf_sr).
nimage
The number of cell images to consider in the computation of the
pair distances. By default, this is zero, meaning that only the
minimum image convention is used.
pospath
The path of the dataset that contains the time dependent data in
the HDF5 file. The first axis of the array must be the time
axis. This is only needed for an off-line analysis
poskey
In case of an on-line analysis, this is the key of the state
item that contains the data from which the RDF is derived.
cellpath
The path the time-dependent cell vector data. This is only
needed when the cell parameters are variable and the analysis is
off-line.
cellkey
The key of the stateitem that contains the cell vectors. This
is only needed when the cell parameters are variable and the
analysis is done on-line.
outpath
The output path for the frequency computation in the HDF5 file.
If not given, it defaults to '%s_rdf' % path. If this path
already exists, it will be removed first.
When f is None, or when the path does not exist in the HDF5 file, the
class can be used as an on-line analysis hook for the iterative
algorithms in yaff.sampling package. This means that the RDF
is built up as the itertive algorithm progresses. The end option is
ignored and max_sample is not applicable to an on-line analysis.
"""
if select0 is not None:
if len(select0) != len(set(select0)):
raise ValueError('No duplicates are allowed in select0')
if len(select0) == 0:
raise ValueError('select0 can not be an empty list')
if select1 is not None:
if len(select1) != len(set(select1)):
raise ValueError('No duplicates are allowed in select1')
if len(select1) == 0:
raise ValueError('select1 can not be an empty list')
if select0 is not None and select1 is not None and len(select0) + len(
select1) != len(set(select0) | set(select1)):
raise ValueError(
'No overlap is allowed between select0 and select1. If you want to compute and RDF within a set of atoms, omit the select1 argument.'
)
if select0 is None and select1 is not None:
raise ValueError('select1 can not be given without select0.')
self.rcut = rcut
self.rspacing = rspacing
self.select0 = select0
self.select1 = select1
self.pairs_sr = self._process_pairs_sr(pairs_sr)
self.nimage = nimage
self.nbin = int(self.rcut / self.rspacing)
self.bins = np.arange(self.nbin + 1) * self.rspacing
self.d = self.bins[:-1] + 0.5 * self.rspacing
self.rdf_sum = np.zeros(self.nbin, float)
self.CN_sum = np.zeros(self.nbin, float)
if self.pairs_sr is not None:
self.rdf_sum_sr = np.zeros(self.nbin, float)
self.nsample = 0
if outpath is None:
outpath = pospath + '_rdf'
analysis_inputs = {
'pos': AnalysisInput(pospath, poskey),
'cell': AnalysisInput(cellpath, cellkey, False)
}
AnalysisHook.__init__(self, f, start, end, max_sample, step,
analysis_inputs, outpath, False)
def __init__(self,
f=None,
start=0,
end=-1,
step=1,
bsize=4096,
select=None,
path='trajectory/vel',
key='vel',
outpath=None,
weights=None):
"""
**Optional arguments:**
f
An h5.File instance containing the trajectory data. If ``f``
is not given, or it does not contain the dataset referred to
with the ``path`` argument, an on-line analysis is carried out.
start
The first sample to be considered for analysis. This may be
negative to indicate that the analysis should start from the
-start last samples.
end
The last sample to be considered for analysis. This may be
negative to indicate that the last -end sample should not be
considered.
step
The spacing between the samples used for the analysis
bsize
The size of the blocks used for individual FFT calls.
select
A list of atom indexes that are considered for the computation
of the spectrum. If not given, all atoms are used.
path
The path of the dataset that contains the time dependent data in
the HDF5 file. The first axis of the array must be the time
axis. The spectra are summed over the other axes.
key
In case of an on-line analysis, this is the key of the state
item that contains the data from which the spectrum is derived.
outpath
The output path for the frequency computation in the HDF5 file.
If not given, it defaults to '%s_spectrum' % path. If this path
already exists, it will be removed first.
weights
If not given, the spectrum is just a simple sum of contributions
from different time-dependent functions. If given, a linear
combination is made based on these weights.
The max_sample argument from get_slice is not used because the choice
step value is an important parameter: it is best to choose step*bsize
such that it coincides with a part of the trajectory in which the
velocities (or other data) are continuous.
The block size should be set such that it corresponds to a decent
resolution on the frequency axis, i.e. 33356 fs of MD data
corresponds to a resolution of about 1 cm^-1. The step size should be
set such that the highest frequency is above the highest relevant
frequency in the spectrum, e.g. a step of 10 fs corresponds to a
frequency maximum of 3336 cm^-1. The total number of FFT's, i.e.
length of the simulation divided by the block size multiplied by the
number of time-dependent functions in the data, determines the noise
reduction on the (the amplitude of) spectrum. If there is sufficient
data to perform 10K FFT's, one should get a reasonably smooth
spectrum.
Depending on the FFT implementation in numpy, it may be interesting
to tune the bsize argument. A power of 2 is typically a good choice.
When f is None, or when the path does not exist in the HDF5 file, the
class can be used as an on-line analysis hook for the iterative
algorithms in yaff.sampling package. This means that the spectrum
is built up as the iterative algorithm progresses. The end option is
ignored for an on-line analysis.
"""
self.bsize = bsize
self.select = select
self.weights = weights
self.ssize = self.bsize // 2 + 1 # the length of the spectrum array
self.amps = np.zeros(self.ssize, float)
self.nfft = 0 # the number of fft calls, for statistics
if outpath is None:
outpath = path + '_spectrum'
analysis_inputs = {'signal': AnalysisInput(path, key)}
AnalysisHook.__init__(self, f, start, end, None, step, analysis_inputs,
outpath, True)
def init_online(self):
AnalysisHook.init_online(self)
self.ncollect = 0
def __init__(self, rcut, rspacing, f=None, start=0, end=-1, max_sample=None,
step=None, select0=None, select1=None, pairs_sr=None, nimage=0,
pospath='trajectory/pos', poskey='pos', cellpath=None,
cellkey=None, outpath=None):
"""Computes a radial distribution function (RDF)
**Argument:**
rcut
The cutoff for the RDF analysis. This should be lower than the
spacing between the primitive cell planes, multiplied by (1+2*nimage).
rspacing
The width of the bins to build up the RDF.
**Optional arguments:**
f
An h5.File instance containing the trajectory data. If ``f``
is not given, or it does not contain the dataset referred to
with the ``path`` argument, an on-line analysis is carried out.
start, end, max_sample, step
arguments to setup the selection of time slices. See
``get_slice`` for more information.
select0
A list of atom indexes that are considered for the computation
of the rdf. If not given, all atoms are used.
select1
A list of atom indexes that are needed to compute an RDF between
two disjoint sets of atoms. (If there is some overlap between
select0 and select1, an error will be raised.) If this is None,
an 'internal' RDF will be computed for the atoms specified in
select0.
pairs_sr
An array with short-range pairs of atoms (shape K x 2). When
given, an additional RDFs is generated for the short-range pairs
(rdf_sr).
nimage
The number of cell images to consider in the computation of the
pair distances. By default, this is zero, meaning that only the
minimum image convention is used.
pospath
The path of the dataset that contains the time dependent data in
the HDF5 file. The first axis of the array must be the time
axis. This is only needed for an off-line analysis
poskey
In case of an on-line analysis, this is the key of the state
item that contains the data from which the RDF is derived.
cellpath
The path the time-dependent cell vector data. This is only
needed when the cell parameters are variable and the analysis is
off-line.
cellkey
The key of the stateitem that contains the cell vectors. This
is only needed when the cell parameters are variable and the
analysis is done on-line.
outpath
The output path for the frequency computation in the HDF5 file.
If not given, it defaults to '%s_rdf' % path. If this path
already exists, it will be removed first.
When f is None, or when the path does not exist in the HDF5 file, the
class can be used as an on-line analysis hook for the iterative
algorithms in yaff.sampling package. This means that the RDF
is built up as the itertive algorithm progresses. The end option is
ignored and max_sample is not applicable to an on-line analysis.
"""
if select0 is not None:
if len(select0) != len(set(select0)):
raise ValueError('No duplicates are allowed in select0')
if len(select0) == 0:
raise ValueError('select0 can not be an empty list')
if select1 is not None:
if len(select1) != len(set(select1)):
raise ValueError('No duplicates are allowed in select1')
if len(select1) == 0:
raise ValueError('select1 can not be an empty list')
if select0 is not None and select1 is not None and len(select0) + len(select1) != len(set(select0) | set(select1)):
raise ValueError('No overlap is allowed between select0 and select1. If you want to compute and RDF within a set of atoms, omit the select1 argument.')
if select0 is None and select1 is not None:
raise ValueError('select1 can not be given without select0.')
self.rcut = rcut
self.rspacing = rspacing
self.select0 = select0
self.select1 = select1
self.pairs_sr = self._process_pairs_sr(pairs_sr)
self.nimage = nimage
self.nbin = int(self.rcut/self.rspacing)
self.bins = np.arange(self.nbin+1)*self.rspacing
self.d = self.bins[:-1] + 0.5*self.rspacing
self.rdf_sum = np.zeros(self.nbin, float)
if self.pairs_sr is not None:
self.rdf_sum_sr = np.zeros(self.nbin, float)
self.nsample = 0
if outpath is None:
outpath = pospath + '_rdf'
analysis_inputs = {'pos': AnalysisInput(pospath, poskey), 'cell': AnalysisInput(cellpath, cellkey, False)}
AnalysisHook.__init__(self, f, start, end, max_sample, step, analysis_inputs, outpath, False)
