def _spectra_from_string(fit_mode, spectra):
if fit_mode == 'bank':
return _parse_spectra_bank(spectra)
else:
if spectra == "forward":
return "{0}-{1}".format(*VESUVIO().forward_spectra)
elif spectra == "backward":
return "{0}-{1}".format(*VESUVIO().backward_spectra)
else:
return spectra
def _parse_spectra_bank(spectra_bank):
if spectra_bank == "forward":
bank_ranges = VESUVIO().forward_banks
elif spectra_bank == "backward":
bank_ranges = VESUVIO()._instrument.backward_banks
else:
raise ValueError("Fitting by bank requires selecting either 'forward' or 'backward' "
"for the spectra to load")
bank_ranges = ["{0}-{1}".format(x, y) for x, y in bank_ranges]
return ";".join(bank_ranges)
def __init__(self, diff_mode, fit_mode, param_file, rebin_params=None, load_log_files=True):
self.fit_mode = fit_mode
self._diff_mode = self._parse_diff_mode(diff_mode)
self._param_file = param_file
self._rebin_params = rebin_params
self._load_log_files = load_log_files
self._instrument = VESUVIO()
def PyExec(self):
"""PyExec is defined by base. It sets the instrument and calls this method
"""
self._INST = VESUVIO()
tof_data = self.getProperty("InputWorkspace").value
reduced_chi_square, fit_params, fit_data = self._fit_tof(tof_data)
self.setProperty("OutputWorkspace", fit_data)
self.setProperty("FitParameters", fit_params)
self.setProperty("Chi2", reduced_chi_square)
def load_and_crop_data(runs, spectra, ip_file, diff_mode='single',
fit_mode='spectra', rebin_params=None):
"""
@param runs The string giving the runs to load
@param spectra A list of spectra to load
@param ip_file A string denoting the IP file
@param diff_mode Either 'double' or 'single'
@param fit_mode If bank then the loading is changed to summing each bank to a separate spectrum
@param rebin_params Rebin parameter string to rebin data by (no rebin if None)
"""
instrument = VESUVIO()
load_banks = (fit_mode == 'bank')
output_name = _create_tof_workspace_suffix(runs, spectra)
if load_banks:
sum_spectra = True
if spectra == "forward":
bank_ranges = instrument.forward_banks
elif spectra == "backward":
bank_ranges = instrument.backward_banks
else:
raise ValueError("Fitting by bank requires selecting either 'forward' or 'backward' "
"for the spectra to load")
bank_ranges = ["{0}-{1}".format(x, y) for x, y in bank_ranges]
spectra = ";".join(bank_ranges)
else:
sum_spectra = False
if spectra == "forward":
spectra = "{0}-{1}".format(*instrument.forward_spectra)
elif spectra == "backward":
spectra = "{0}-{1}".format(*instrument.backward_spectra)
if diff_mode == "double":
diff_mode = "DoubleDifference"
else:
diff_mode = "SingleDifference"
kwargs = {"Filename": runs,
"Mode": diff_mode, "InstrumentParFile": ip_file,
"SpectrumList": spectra, "SumSpectra": sum_spectra,
"OutputWorkspace": output_name}
full_range = ms.LoadVesuvio(**kwargs)
tof_data = ms.CropWorkspace(InputWorkspace=full_range,
XMin=instrument.tof_range[0],
XMax=instrument.tof_range[1],
OutputWorkspace=output_name)
if rebin_params is not None:
tof_data = ms.Rebin(InputWorkspace=tof_data,
OutputWorkspace=output_name,
Params=rebin_params)
return tof_data
def _get_properties(self):
self._input_ws = self.getProperty("InputWorkspace").value
self._container_ws = self.getPropertyValue("ContainerWorkspace")
self._spec_idx = self.getProperty("WorkspaceIndex").value
self._output_ws = self.getPropertyValue("OutputWorkspace")
self._correction_wsg = self.getPropertyValue("CorrectionWorkspaces")
self._corrected_wsg = self.getPropertyValue("CorrectedWorkspaces")
self._linear_fit_table = self.getPropertyValue("LinearFitResult")
self._masses = self.getProperty("Masses").value
self._index_to_symbol_map = self.getProperty(
"MassIndexToSymbolMap").value
self._hydrogen_constraints = self.getProperty(
"HydrogenConstraints").value
spec_no = self._input_ws.getSpectrum(self._spec_idx).getSpectrumNo()
back_spectra = VESUVIO().backward_spectra
self._back_scattering = back_spectra[0] <= spec_no <= back_spectra[1]
def is_back_scattering_spectra(spectra):
"""
Checks whether the specified spectra denotes back scattering spectra.
:param spectra: The spectra to check.
:return: True if the specified spectra denotes back scattering
spectra.
"""
if spectra == 'forward':
return False
elif spectra == 'backward':
return True
else:
try:
first_spectrum = int(spectra.split("-")[0])
return any([lower <= first_spectrum <= upper for lower, upper in VESUVIO().backward_banks])
except:
raise RuntimeError("Invalid value given for spectrum range: Range must "
"either be 'forward', 'backward' or specified with "
"the syntax 'a-b'.")
def fit_tof(runs, flags, iterations=1, convergence_threshold=None):
"""
The main entry point for user scripts fitting in TOF.
:param runs: A string specifying the runs to process, or a workspace containing
the loaded runs
:param flags: A dictionary of flags to control the processing
:param iterations: Maximum number of iterations to perform
:param convergence_threshold: Maximum difference in the cost
function at which the parameters are accepted
to have converged
:return: Tuple of (fitted workspace, fitted params, number of iterations
performed)
"""
if iterations < 1:
raise ValueError('Must perform at least one iteration')
# Load
fit_mode = flags['fit_mode']
back_banks = VESUVIO().backward_banks
if isinstance(runs, MatrixWorkspace):
sample_data = runs
flags['runs'] = runs.getName()
flags['spectra'] = sample_data.getAxis(0).extractValues()
flags['back_scattering'] = any([
lower <= flags['spectra'][0] <= upper
for lower, upper in back_banks
])
else:
spectra = flags['spectra']
sample_data = load_and_crop_data(runs, spectra, flags['ip_file'],
flags['diff_mode'], fit_mode,
flags.get('bin_parameters', None))
flags['runs'] = runs
if spectra == 'backward' or spectra == 'forward':
flags['back_scattering'] = spectra == 'backward'
else:
try:
first_spec = int(spectra.split("-")[0])
flags['back_scattering'] = any([
lower <= first_spec <= upper for lower, upper in back_banks
])
except:
raise RuntimeError(
"Invalid value given for spectrum range: Range must either be 'forward', "
"'backward' or specified with the syntax 'a-b'.")
# Load container runs if provided
container_data = None
if flags.get('container_runs', None) is not None:
if isinstance(flags['container_runs'], MatrixWorkspace):
container_data = flags['container_runs']
else:
container_data = load_and_crop_data(
flags['container_runs'], spectra,
flags['ip_file'], flags['diff_mode'], fit_mode,
flags.get('bin_parameters', None))
return fit_tof_impl(sample_data, container_data, flags, iterations,
convergence_threshold)
def fit_tof(runs, flags, iterations=1, convergence_threshold=None):
"""
The main entry point for user scripts fitting in TOF.
:param runs: A string specifying the runs to process
:param flags: A dictionary of flags to control the processing
:param iterations: Maximum number of iterations to perform
:param convergence_threshold: Maximum difference in the cost
function at which the parameters are accepted
to have converged
:return: Tuple of (fitted workspace, fitted params, number of iterations
performed)
"""
if iterations < 1:
raise ValueError('Must perform at least one iteration')
# Load
spectra = flags['spectra']
fit_mode = flags['fit_mode']
sample_data = load_and_crop_data(runs, spectra, flags['ip_file'],
flags['diff_mode'], fit_mode,
flags.get('bin_parameters', None))
# Load container runs if provided
container_data = None
if flags.get('container_runs', None) is not None:
container_data = load_and_crop_data(flags['container_runs'], spectra,
flags['ip_file'],
flags['diff_mode'], fit_mode,
flags.get('bin_parameters', None))
# Check if multiple scattering flags have been defined
if 'ms_flags' in flags:
# Check if hydrogen constraints have been defined
if 'HydrogenConstraints' in flags['ms_flags']:
flags['ms_flags']['HydrogenConstraints'] = \
_parse_ms_hydrogen_constraints(flags['ms_flags']['HydrogenConstraints'])
else:
flags['ms_flags']['HydrogenConstraints'] = dict()
else:
raise RuntimeError(
"Multiple scattering flags not provided. Set the ms_flag, 'ms_enabled' "
"to false, in order to disable multiple scattering corrections.")
if spectra == 'backward' or spectra == 'forward':
flags['back_scattering'] = spectra == 'backward'
else:
try:
first_spec = int(spectra.split("-")[0])
back_banks = VESUVIO().backward_banks
flags['back_scattering'] = any(
[lower <= first_spec <= upper for lower, upper in back_banks])
except:
raise RuntimeError(
"Invalid value given for spectrum range: Range must either be 'forward', "
"'backward' or specified with the syntax 'a-b'.")
last_results = None
exit_iteration = 0
index_to_symbol_map = filter(lambda x: 'symbol' in x[1],
enumerate(flags['masses']))
index_to_symbol_map = {str(k): v['symbol'] for k, v in index_to_symbol_map}
hydrogen_indices = set()
if flags['back_scattering']:
hydrogen_indices = {
int(k)
for k, _ in filter(lambda x: x[1] == 'H',
index_to_symbol_map.items())
}
symbols = set()
for symbol in flags['ms_flags']['HydrogenConstraints']:
symbols.add(symbol)
for symbol in index_to_symbol_map.values():
symbols.discard(symbol)
if symbols:
raise RuntimeError(
"HydrogenConstraints contains references to the following,"
" undefined masses: " + ','.join(symbols))
flags['index_to_symbol_map'] = index_to_symbol_map
for iteration in range(1, iterations + 1):
iteration_flags = copy.deepcopy(flags)
iteration_flags['iteration'] = iteration
if last_results is not None:
iteration_flags['masses'] = _update_masses_from_params(
copy.deepcopy(flags['masses']),
last_results[2],
ignore_indices=hydrogen_indices)
print("=== Iteration {0} out of a possible {1}".format(
iteration, iterations))
results = fit_tof_iteration(sample_data, container_data, runs,
iteration_flags)
exit_iteration += 1
if last_results is not None and convergence_threshold is not None:
last_chi2 = np.array(last_results[3])
chi2 = np.array(results[3])
chi2_delta = last_chi2 - chi2
max_chi2_delta = np.abs(np.max(chi2_delta))
print("Cost function change: {0}".format(max_chi2_delta))
if max_chi2_delta <= convergence_threshold:
print(
"Stopped at iteration {0} due to minimal change in cost function"
.format(exit_iteration))
last_results = results
break
last_results = results
return last_results[0], last_results[2], last_results[3], exit_iteration
