def normalize_transmission(self, im: Exposure, datared: Dict):
transmission = im.header.transmission
im /= im.header.transmission
datared['history'].append('Divided by transmission: ' + str(im.header.transmission))
datared['statistics']['04_normalize_transmission'] = im.get_statistics()
self._logger.debug('Done normalizing by transmission FSN {:d}'.format(im.header.fsn))
return im, datared
def subtractemptybeambackground(self, im: Exposure, datared: Dict):
if im.header.title == self.config['datareduction']['backgroundname']:
self._lastbackground = im
self._logger.debug('Done bgsub FSN {:d}: this is background'.format(im.header.fsn))
datared['history'].append('This is an empty beam measurement.')
raise DataReductionEnd()
if ((im.header.distance - self._lastbackground.header.distance).abs() <
self.config['datareduction']['distancetolerance']):
im -= self._lastbackground
datared['history'].append(
'Subtracted background FSN #{:d}'.format(self._lastbackground.header.fsn))
datared['emptybeamFSN'] = self._lastbackground.header.fsn
else:
raise ServiceError('Last seen background measurement does not match the exposure under reduction.')
datared['statistics']['05_subtractbackground'] = im.get_statistics()
self._logger.debug('Done bgsub FSN {:d}'.format(im.header.fsn))
return im, datared
def subtractdarkbackground(self, im: Exposure, datared: Dict):
if im.header.title == self.config['datareduction']['darkbackgroundname']:
self._lastdarkbackground = im.mean()
self._logger.debug('Determined background level: {:g} cps per pixel'.format(self._lastdarkbackground))
self._logger.debug('Done darkbgsub FSN {:d}: this is dark background'.format(im.header.fsn))
datared['history'].append(
'This is a dark background measurement. Level: {:g} cps per pixel (overall {:g} cps)'.format(
self._lastdarkbackground, self._lastdarkbackground * im.shape[0] * im.shape[1]))
raise DataReductionEnd()
# otherwise subtract the background.
im -= self._lastdarkbackground
datared['history'].append(
'Subtracted dark background level: {:g} cps per pixel (overall {:g} cps)'.format(
self._lastdarkbackground, self._lastdarkbackground * im.shape[0] * im.shape[1]))
datared['darkbackgroundlevel'] = self._lastdarkbackground
datared['statistics']['03_subtractdarkbackground'] = im.get_statistics()
self._logger.debug('Done darkbgsub FSN {:d}'.format(im.header.fsn))
return im, datared
def correctgeometry(self, im: Exposure, datared: Dict):
tth = im.twotheta
assert isinstance(tth, ErrorValue)
datared['tthval_statistics'] = self.get_matrix_statistics(tth.val)
datared['ttherr_statistics'] = self.get_matrix_statistics(tth.err)
assert im.header.pixelsizex == im.header.pixelsizey
corr_sa = solidangle(tth.val, tth.err, im.header.distance.val,
im.header.distance.err, im.header.pixelsizex)
im *= corr_sa
datared['history'].append('Corrected for solid angle')
datared['solidangle_matrixval_statistics'] = self.get_matrix_statistics(corr_sa.val)
datared['solidangle_matrixerr_statistics'] = self.get_matrix_statistics(corr_sa.err)
corr_ada = angledependentabsorption(tth.val, tth.err, im.header.transmission.val,
im.header.transmission.err)
im *= corr_ada
datared['angledependentabsorption_matrixval_statistics'] = self.get_matrix_statistics(
corr_ada.val)
datared['angledependentabsorption_matrixerr_statistics'] = self.get_matrix_statistics(
corr_ada.err)
datared['history'].append('Corrected for angle-dependent absorption')
try:
vacuum = im.header.vacuum
except KeyError:
datared['history'].append(
'Skipped angle-dependent air absorption correction: no pressure value.')
else:
corr_adat = angledependentairtransmission(tth.val, tth.err, vacuum,
im.header.distance.val,
im.header.distance.err,
self.config['datareduction']['mu_air'],
self.config['datareduction']['mu_air.err'])
im *= corr_adat
datared[
'angledependentairtransmission_matrixval_statistics'] = self.get_matrix_statistics(corr_adat.val)
datared[
'angledependentairtransmission_matrixerr_statistics'] = self.get_matrix_statistics(corr_adat.err)
datared['history'].append(
'Corrected for angle-dependent air absorption. Pressure: {:f} mbar'.format(
im.header.vacuum))
datared['statistics']['06_correctgeometry'] = im.get_statistics()
self._logger.debug('Done correctgeometry FSN {:d}'.format(im.header.fsn))
return im, datared
def datareduction(self, intensity: np.ndarray, mask: np.ndarray, params: dict):
im = Exposure(intensity, intensity ** 0.5, Header(params), mask)
im.mask_negative()
im.mask_nonfinite()
im.mask_nan()
self._logger.debug('Commencing data reduction of FSN #{:d} (sample {}).'.format(im.header.fsn, im.header.title))
datared = {'history': [], 'statistics': {'01_initial': im.get_statistics()}}
try:
self.normalize_flux(im, datared)
self.subtractdarkbackground(im, datared)
self.normalize_transmission(im, datared)
self.subtractemptybeambackground(im, datared)
self.correctgeometry(im, datared)
self.dividebythickness(im, datared)
self.absolutescaling(im, datared)
except DataReductionEnd:
pass
self._logger.info('Data reduction history for FSN #{:d}:\n '.format(im.header.fsn) +
'\n '.join(h for h in datared['history']))
im.header.param['datareduction'] = datared
return im
def absolutescaling(self, im: Exposure, datared: Dict):
if im.header.title == self.config['datareduction']['absintrefname']:
self._logger.debug('History: {}'.format('\n'.join([h for h in datared['history']])))
dataset = np.loadtxt(self.config['datareduction']['absintrefdata'])
self._logger.debug('Q-range of absint dataset: {:g} to {:g}, {:d} points.'.format(
dataset[:, 0].min(), dataset[:, 0].max(), len(dataset[:, 0])))
testradavg = im.radial_average()
self._logger.debug('Auto-Q-range of the measured dataset: {:g} to {:g}, {:d} points.'.format(
testradavg.q.min(), testradavg.q.max(), len(testradavg)))
# noinspection PyPep8Naming,PyPep8Naming
q, dq, I, dI, area = im.radial_average(qrange=dataset[:, 0], raw_result=True)
dataset = dataset[area > 0, :]
# noinspection PyPep8Naming
I = I[area > 0]
# noinspection PyPep8Naming
dI = dI[area > 0]
q = q[area > 0]
self._logger.debug('Common q-range: {:g} to {:g}, {:d} points.'.format(q.min(), q.max(), len(q)))
scalingfactor, stat = nonlinear_odr(I, dataset[:, 1], dI, dataset[:, 2], lambda x, a: a * x, [1])
datared['absintscaling'] = {'q': q, 'area': area, 'Imeas': I, 'dImeas': dI,
'Iref': dataset[:, 1], 'dIref': dataset[:, 2],
'factor.val': scalingfactor.val,
'factor.err': scalingfactor.err, 'stat': stat}
self._logger.debug('Scaling factor: ' + str(scalingfactor))
self._logger.debug('Chi2: {:f}'.format(stat['Chi2_reduced']))
self._lastabsintref = im
self._absintscalingfactor = scalingfactor
self._absintstat = stat
self._absintqrange = q
datared['history'].append(
'This is an absolute intensity reference measurement. '
'Determined absolute intensity scaling factor: {}. Reduced Chi2: {:f}. DoF: {:d}. '
'This corresponds to beam flux {} photons*eta/sec'.format(
self._absintscalingfactor, self._absintstat['Chi2_reduced'], self._absintstat['DoF'],
1 / self._absintscalingfactor))
if ((im.header.distance - self._lastabsintref.header.distance).abs() <
self.config['datareduction']['distancetolerance']):
im *= self._absintscalingfactor
datared['statistics']['08_absolutescaling'] = im.get_statistics()
datared['history'].append(
'Using absolute intensity factor {} from measurement FSN #{:d} '
'for absolute intensity calibration.'.format(
self._absintscalingfactor, self._lastabsintref.header.fsn))
datared['history'].append('Absint factor was determined with Chi2 {:f} (DoF {:d})'.format(
self._absintstat['Chi2_reduced'], self._absintstat['DoF']))
datared['history'].append('Estimated flux: {} photons*eta/sec'.format(
self._absintscalingfactor.__reciprocal__()))
datared['absintrefFSN'] = self._lastabsintref.header.fsn
datared['flux'] = self._absintscalingfactor.__reciprocal__().val
datared['flux.err'] = self._absintscalingfactor.__reciprocal__().err
datared['absintchi2'] = self._absintstat['Chi2_reduced']
datared['absintdof'] = self._absintstat['DoF']
datared['absintfactor'] = self._absintscalingfactor.val
datared['absintfactor.err'] = self._absintscalingfactor.err
datared['absintqmin'] = self._absintqrange.min()
datared['absintqmax'] = self._absintqrange.max()
else:
raise ServiceError(
'S-D distance of the last seen absolute intensity reference measurement '
'does not match the exposure under reduction.')
self._logger.debug('Done absint FSN ' + str(im.header.fsn))
return im, datared
def dividebythickness(self, im: Exposure, datared: Dict):
im /= im.header.thickness
datared['history'].append('Divided by thickness {:g} cm'.format(im.header.thickness))
datared['statistics']['07_dividebythickness'] = im.get_statistics()
self._logger.debug('Done dividebythickness FSN {:d}'.format(im.header.fsn))
return im, datared
def normalize_flux(self, im: Exposure, datared: Dict):
im /= im.header.exposuretime
datared['history'].append('Divided by exposure time')
datared['statistics']['02_normalize_flux'] = im.get_statistics()
self._logger.debug('Done normalizing by flux FSN {:d}'.format(im.header.fsn))
return im, datared