def process_dgs_data(obj, conf, bcan, ecan, tcoeff, **kwargs):
"""
This function combines Steps 7 through 16 in Section 2.1.1 of the data
reduction process for Direct Geometry Spectrometers as specified by the
document at
U{http://neutrons.ornl.gov/asg/projects/SCL/reqspec/DR_Lib_RS.doc}. The
function takes a calibrated dataset, a L{hlr_utils.Configure} object and
processes the data accordingly.
@param obj: A calibrated dataset object.
@type obj: C{SOM.SOM}
@param conf: Object that contains the current setup of the driver.
@type conf: L{hlr_utils.Configure}
@param bcan: The object containing the black can data.
@type bcan: C{SOM.SOM}
@param ecan: The object containing the empty can data.
@type ecan: C{SOM.SOM}
@param tcoeff: The transmission coefficient appropriate to the given data
set.
@type tcoeff: C{tuple}
@param kwargs: A list of keyword arguments that the function accepts:
@keyword dataset_type: The practical name of the dataset being processed.
The default value is I{data}.
@type dataset_type: C{string}
@keyword cwp_used: A flag signalling the use of the chopper phase
corrections.
@type cwp_used: C{bool}
@keyword timer: Timing object so the function can perform timing estimates.
@type timer: C{sns_timer.DiffTime}
@return: Object that has undergone all requested processing steps
@rtype: C{SOM.SOM}
"""
import array_manip
import common_lib
import dr_lib
import hlr_utils
# Check keywords
try:
dataset_type = kwargs["dataset_type"]
except KeyError:
dataset_type = "data"
try:
t = kwargs["timer"]
except KeyError:
t = None
cwp_used = kwargs.get("cwp_used", False)
if conf.verbose:
print "Processing %s information" % dataset_type
# Step 7: Create black can background contribution
if bcan is not None:
if conf.verbose:
print "Creating black can background contribution for %s" \
% dataset_type
if t is not None:
t.getTime(False)
bccoeff = array_manip.sub_ncerr(1.0, 0.0, tcoeff[0], tcoeff[1])
bcan1 = common_lib.mult_ncerr(bcan, bccoeff)
if t is not None:
t.getTime(msg="After creating black can background contribution ")
del bcan
else:
bcan1 = None
# Step 8: Create empty can background contribution
if ecan is not None:
if conf.verbose:
print "Creating empty can background contribution for %s" \
% dataset_type
if t is not None:
t.getTime(False)
ecan1 = common_lib.mult_ncerr(ecan, tcoeff)
if t is not None:
t.getTime(msg="After creating empty can background contribution ")
del ecan
else:
ecan1 = None
# Step 9: Create background spectra
if bcan1 is not None or ecan1 is not None and conf.verbose:
print "Creating background spectra for %s" % dataset_type
if bcan1 is not None and ecan1 is not None:
if cwp_used:
if conf.verbose:
print "Rebinning empty can to black can axis."
ecan2 = common_lib.rebin_axis_1D_frac(ecan1, bcan1[0].axis[0].val)
else:
ecan2 = ecan1
del ecan1
if t is not None:
t.getTime(False)
b_som = common_lib.add_ncerr(bcan1, ecan2)
if t is not None:
t.getTime(msg="After creating background spectra ")
elif bcan1 is not None and ecan1 is None:
b_som = bcan1
elif bcan1 is None and ecan1 is not None:
b_som = ecan1
else:
b_som = None
del bcan1, ecan1
if cwp_used:
if conf.verbose:
print "Rebinning background spectra to %s" % dataset_type
b_som1 = common_lib.rebin_axis_1D_frac(b_som, obj[0].axis[0].val)
else:
b_som1 = b_som
del b_som
if conf.dump_ctof_comb and b_som1 is not None:
b_som_1 = dr_lib.sum_all_spectra(b_som1)
hlr_utils.write_file(conf.output,
"text/Spec",
b_som_1,
output_ext="ctof",
extra_tag="background",
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
verbose=conf.verbose,
message="combined background TOF information")
del b_som_1
# Step 10: Subtract background from data
obj1 = dr_lib.subtract_bkg_from_data(obj,
b_som1,
verbose=conf.verbose,
timer=t,
dataset1=dataset_type,
dataset2="background")
del obj, b_som1
# Step 11: Calculate initial velocity
if conf.verbose:
print "Calculating initial velocity"
if t is not None:
t.getTime(False)
if conf.initial_energy is not None:
initial_wavelength = common_lib.energy_to_wavelength(\
conf.initial_energy.toValErrTuple())
initial_velocity = common_lib.wavelength_to_velocity(\
initial_wavelength)
else:
# This should actually calculate it, but don't have a way right now
pass
if t is not None:
t.getTime(msg="After calculating initial velocity ")
# Step 12: Calculate the time-zero offset
if conf.time_zero_offset is not None:
time_zero_offset = conf.time_zero_offset.toValErrTuple()
else:
# This should actually calculate it, but don't have a way right now
time_zero_offset = (0.0, 0.0)
# Step 13: Convert time-of-flight to final velocity
if conf.verbose:
print "Converting TOF to final velocity DGS"
if t is not None:
t.getTime(False)
obj2 = common_lib.tof_to_final_velocity_dgs(obj1,
initial_velocity,
time_zero_offset,
units="microsecond")
if t is not None:
t.getTime(msg="After calculating TOF to final velocity DGS ")
del obj1
# Step 14: Convert final velocity to final wavelength
if conf.verbose:
print "Converting final velocity DGS to final wavelength"
if t is not None:
t.getTime(False)
obj3 = common_lib.velocity_to_wavelength(obj2)
if t is not None:
t.getTime(msg="After calculating velocity to wavelength ")
del obj2
if conf.dump_wave_comb:
obj3_1 = dr_lib.sum_all_spectra(
obj3, rebin_axis=conf.lambda_bins.toNessiList())
hlr_utils.write_file(conf.output,
"text/Spec",
obj3_1,
output_ext="fwv",
extra_tag=dataset_type,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
verbose=conf.verbose,
message="combined final wavelength information")
del obj3_1
# Step 15: Create the detector efficiency
if conf.det_eff is not None:
if conf.verbose:
print "Creating detector efficiency spectra"
if t is not None:
t.getTime(False)
det_eff = dr_lib.create_det_eff(obj3)
if t is not None:
t.getTime(msg="After creating detector efficiency spectra ")
else:
det_eff = None
# Step 16: Divide the detector pixel spectra by the detector efficiency
if det_eff is not None:
if conf.verbose:
print "Correcting %s for detector efficiency" % dataset_type
if t is not None:
t.getTime(False)
obj4 = common_lib.div_ncerr(obj3, det_eff)
if t is not None:
t.getTime(msg="After correcting %s for detector efficiency" \
% dataset_type)
else:
obj4 = obj3
del obj3, det_eff
return obj4
def process_sas_data(datalist, conf, **kwargs):
"""
This function combines Steps 1 through 9 of the data reduction process for
Small-Angle Scattering section 2.5.1 as specified by the documents at
U{http://neutrons.ornl.gov/asg/projects/SCL/reqspec/DR_Lib_RS.doc}. The
function takes a list of file names, a L{hlr_utils.Configure} object and
processes the data accordingly. This function should really only be used in
the context of I{sas_reduction}.
@param datalist: A list containing the filenames of the data to be
processed.
@type datalist: C{list} of C{string}s
@param conf: Object that contains the current setup of the driver.
@type conf: L{hlr_utils.Configure}
@param kwargs: A list of keyword arguments that the function accepts:
@keyword inst_geom_dst: File object that contains instrument geometry
information.
@type inst_geom_dst: C{DST.GeomDST}
@keyword dataset_type: The practical name of the dataset being processed.
The default value is I{data}.
@type dataset_type: C{string}
@keyword trans_data: Alternate data for the transmission spectrum. This is
used in the absence of transmission monitors.
@type trans_data: C{string}
@keyword transmission: A flag that signals the function to stop after
doing the conversion from TOF to wavelength. The
default is I{False}.
@type transmission: C{boolean}
@keyword bkg_subtract: A list of coefficients that help determine the
wavelength dependent background subtraction.
@type bkg_subtract: C{list}
@keyword get_background: A flag that signals the function to convert the
main data to wavelength and exit before
normalizing to the beam monitor.
@type get_background: C{boolean}
@keyword acc_down_time: The information for the accelerator downtime.
@type acc_down_time: C{tuple}
@keyword bkg_scale: The scaling used for the axis dependent background
parameters.
@type bkg_scale: C{float}
@keyword timer: Timing object so the function can perform timing estimates.
@type timer: C{sns_timer.DiffTime}
@return: Object that has undergone all requested processing steps
@rtype: C{SOM.SOM}
"""
import common_lib
import dr_lib
import hlr_utils
# Check keywords
try:
dataset_type = kwargs["dataset_type"]
except KeyError:
dataset_type = "data"
try:
i_geom_dst = kwargs["inst_geom_dst"]
except KeyError:
i_geom_dst = None
try:
t = kwargs["timer"]
except KeyError:
t = None
try:
transmission = kwargs["transmission"]
except KeyError:
transmission = False
try:
bkg_subtract = kwargs["bkg_subtract"]
except KeyError:
bkg_subtract = None
try:
trans_data = kwargs["trans_data"]
except KeyError:
trans_data = None
try:
get_background = kwargs["get_background"]
except KeyError:
get_background = False
acc_down_time = kwargs.get("acc_down_time")
bkg_scale = kwargs.get("bkg_scale")
# Add so_axis to Configure object
conf.so_axis = "time_of_flight"
# Step 0: Open appropriate data files
# Data
if conf.verbose:
print "Reading %s file" % dataset_type
# The [0] is to get the data SOM and ignore the None background SOM
dp_som = dr_lib.add_files(datalist, Data_Paths=conf.data_paths.toPath(),
SO_Axis=conf.so_axis, Signal_ROI=conf.roi_file,
dataset_type=dataset_type,
Verbose=conf.verbose, Timer=t)
if t is not None:
t.getTime(msg="After reading %s " % dataset_type)
dp_som1 = dr_lib.fix_bin_contents(dp_som)
del dp_som
if conf.inst_geom is not None:
i_geom_dst.setGeometry(conf.data_paths.toPath(), dp_som1)
if conf.dump_tof_r:
dp_som1_1 = dr_lib.create_param_vs_Y(dp_som1, "radius", "param_array",
conf.r_bins.toNessiList(),
y_label="counts",
y_units="counts / (usec * m)",
x_labels=["Radius", "TOF"],
x_units=["m", "usec"])
hlr_utils.write_file(conf.output, "text/Dave2d", dp_som1_1,
output_ext="tvr",
extra_tag=dataset_type,
verbose=conf.verbose,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
message="TOF vs radius information")
del dp_som1_1
if conf.dump_tof_theta:
dp_som1_1 = dr_lib.create_param_vs_Y(dp_som1, "polar", "param_array",
conf.theta_bins.toNessiList(),
y_label="counts",
y_units="counts / (usec * rads)",
x_labels=["Polar Angle", "TOF"],
x_units=["rads", "usec"])
hlr_utils.write_file(conf.output, "text/Dave2d", dp_som1_1,
output_ext="tvt",
extra_tag=dataset_type,
verbose=conf.verbose,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
message="TOF vs polar angle information")
del dp_som1_1
# Beam monitor
if not get_background:
if conf.beammon_over is None:
if conf.verbose:
print "Reading in beam monitor data from %s file" \
% dataset_type
# The [0] is to get the data SOM and ignore the None
# background SOM
dbm_som0 = dr_lib.add_files(datalist,
Data_Paths=conf.bmon_path.toPath(),
SO_Axis=conf.so_axis,
dataset_type=dataset_type,
Verbose=conf.verbose,
Timer=t)
if t is not None:
t.getTime(msg="After reading beam monitor data ")
if conf.inst_geom is not None:
i_geom_dst.setGeometry(conf.bmon_path.toPath(), dbm_som0)
else:
if conf.verbose:
print "Reading in vanadium data"
dbm_som0 = dr_lib.add_files(datalist,
Data_Paths=conf.data_paths.toPath(),
Signal_ROI=conf.roi_file,
SO_Axis=conf.so_axis,
dataset_type=dataset_type,
Verbose=conf.verbose,
Timer=t)
if t is not None:
t.getTime(msg="After reading vanadium data ")
if conf.inst_geom is not None:
i_geom_dst.setGeometry(conf.data_paths.toPath(), dbm_som0)
dbm_som1 = dr_lib.fix_bin_contents(dbm_som0)
del dbm_som0
else:
dbm_som1 = None
# Transmission monitor
if trans_data is None:
if conf.verbose:
print "Reading in transmission monitor data from %s file" \
% dataset_type
try:
dtm_som0 = dr_lib.add_files(datalist,
Data_Paths=conf.tmon_path.toPath(),
SO_Axis=conf.so_axis,
dataset_type=dataset_type,
Verbose=conf.verbose,
Timer=t)
if t is not None:
t.getTime(msg="After reading transmission monitor data ")
if conf.inst_geom is not None:
i_geom_dst.setGeometry(conf.tmon_path.toPath(), dtm_som0)
dtm_som1 = dr_lib.fix_bin_contents(dtm_som0)
del dtm_som0
# Transmission monitor cannot be found
except KeyError:
if conf.verbose:
print "Transmission monitor not found"
dtm_som1 = None
else:
dtm_som1 = None
# Note: time_zero_offset_det MUST be a tuple
if conf.time_zero_offset_det is not None:
dp_som1.attr_list["Time_zero_offset_det"] = \
conf.time_zero_offset_det.toValErrTuple()
# Note: time_zero_offset_mon MUST be a tuple
if conf.time_zero_offset_mon is not None and not get_background and \
conf.beammon_over is None:
dbm_som1.attr_list["Time_zero_offset_mon"] = \
conf.time_zero_offset_mon.toValErrTuple()
if conf.beammon_over is not None:
dbm_som1.attr_list["Time_zero_offset_det"] = \
conf.time_zero_offset_det.toValErrTuple()
if trans_data is None and dtm_som1 is not None:
dtm_som1.attr_list["Time_zero_offset_mon"] = \
conf.time_zero_offset_mon.toValErrTuple()
# Step 1: Convert TOF to wavelength for data and monitor
if conf.verbose:
print "Converting TOF to wavelength"
if t is not None:
t.getTime(False)
if not get_background:
# Convert beam monitor
if conf.beammon_over is None:
dbm_som2 = common_lib.tof_to_wavelength_lin_time_zero(
dbm_som1,
units="microsecond",
time_zero_offset=conf.time_zero_offset_mon.toValErrTuple())
else:
dbm_som2 = common_lib.tof_to_wavelength_lin_time_zero(
dbm_som1,
units="microsecond",
time_zero_offset=conf.time_zero_offset_det.toValErrTuple(),
inst_param="total")
else:
dbm_som2 = None
# Convert detector pixels
dp_som2 = common_lib.tof_to_wavelength_lin_time_zero(
dp_som1,
units="microsecond",
time_zero_offset=conf.time_zero_offset_det.toValErrTuple(),
inst_param="total")
if get_background:
return dp_som2
if dtm_som1 is not None:
# Convert transmission monitor
dtm_som2 = common_lib.tof_to_wavelength_lin_time_zero(
dtm_som1,
units="microsecond",
time_zero_offset=conf.time_zero_offset_mon.toValErrTuple())
else:
dtm_som2 = dtm_som1
if t is not None:
t.getTime(msg="After converting TOF to wavelength ")
del dp_som1, dbm_som1, dtm_som1
if conf.verbose and (conf.lambda_low_cut is not None or \
conf.lambda_high_cut is not None):
print "Cutting data spectra"
if t is not None:
t.getTime(False)
dp_som3 = dr_lib.cut_spectra(dp_som2, conf.lambda_low_cut,
conf.lambda_high_cut)
if t is not None:
t.getTime(msg="After cutting data spectra ")
del dp_som2
if conf.beammon_over is not None:
dbm_som2 = dr_lib.cut_spectra(dbm_som2, conf.lambda_low_cut,
conf.lambda_high_cut)
if conf.dump_wave:
hlr_utils.write_file(conf.output, "text/Spec", dp_som3,
output_ext="pxl",
extra_tag=dataset_type,
verbose=conf.verbose,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
message="pixel wavelength information")
if conf.dump_bmon_wave:
if conf.beammon_over is None:
hlr_utils.write_file(conf.output, "text/Spec", dbm_som2,
output_ext="bmxl",
extra_tag=dataset_type,
verbose=conf.verbose,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
message="beam monitor wavelength information")
else:
dbm_som2_1 = dr_lib.sum_by_rebin_frac(dbm_som2,
conf.lambda_bins.toNessiList())
hlr_utils.write_file(conf.output, "text/Spec", dbm_som2_1,
output_ext="bmxl",
extra_tag=dataset_type,
verbose=conf.verbose,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
message="beam monitor override wavelength "\
+"information")
del dbm_som2_1
# Step 2: Subtract wavelength dependent background if necessary
if conf.verbose and bkg_subtract is not None:
print "Subtracting wavelength dependent background"
if bkg_subtract is not None:
if t is not None:
t.getTime(False)
duration = dp_som3.attr_list["%s-duration" % dataset_type]
scale = duration.getValue() - acc_down_time[0]
dp_som4 = dr_lib.subtract_axis_dep_bkg(dp_som3, bkg_subtract,
old_scale=bkg_scale,
new_scale=scale)
if t is not None:
t.getTime(msg="After subtracting wavelength dependent background ")
else:
dp_som4 = dp_som3
del dp_som3
# Step 3: Efficiency correct beam monitor
if conf.verbose and conf.mon_effc:
print "Efficiency correct beam monitor data"
if t is not None:
t.getTime(False)
if conf.mon_effc:
dbm_som3 = dr_lib.feff_correct_mon(dbm_som2, inst_name=conf.inst,
eff_const=conf.mon_eff_const)
else:
dbm_som3 = dbm_som2
if t is not None and conf.mon_effc:
t.getTime(msg="After efficiency correcting beam monitor ")
if conf.dump_bmon_effc and conf.mon_effc:
hlr_utils.write_file(conf.output, "text/Spec", dbm_som3,
output_ext="bmel",
extra_tag=dataset_type,
verbose=conf.verbose,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
message="beam monitor wavelength information "\
+"(efficiency)")
del dbm_som2
# Step 4: Efficiency correct transmission monitor
if dtm_som2 is not None:
if conf.verbose and conf.mon_effc:
print "Efficiency correct transmission monitor data"
if t is not None:
t.getTime(False)
if conf.mon_effc:
dtm_som3 = dr_lib.feff_correct_mon(dtm_som2)
else:
dtm_som3 = dtm_som2
else:
dtm_som3 = dtm_som2
if t is not None and conf.mon_effc and dtm_som2 is not None:
t.getTime(msg="After efficiency correcting beam monitor ")
# Step 5: Efficiency correct detector pixels
if conf.det_effc:
if conf.verbose:
print "Calculating detector efficiency"
if t is not None:
t.getTime(False)
det_eff = dr_lib.create_det_eff(dp_som4, inst_name=conf.inst,
eff_scale_const=conf.det_eff_scale_const,
eff_atten_const=conf.det_eff_atten_const)
if t is not None:
t.getTime(msg="After calculating detector efficiency")
if conf.verbose:
print "Applying detector efficiency"
if t is not None:
t.getTime(False)
dp_som5 = common_lib.div_ncerr(dp_som4, det_eff)
if t is not None:
t.getTime(msg="After spplying detector efficiency")
else:
dp_som5 = dp_som4
del dp_som4
# Step 6: Rebin beam monitor axis onto detector pixel axis
if conf.beammon_over is None:
if not conf.no_bmon_norm:
if conf.verbose:
print "Rebin beam monitor axis to detector pixel axis"
if t is not None:
t.getTime(False)
dbm_som4 = dr_lib.rebin_monitor(dbm_som3, dp_som5, rtype="frac")
if t is not None:
t.getTime(msg="After rebinning beam monitor ")
else:
dbm_som4 = dbm_som3
else:
dbm_som4 = dbm_som3
del dbm_som3
if conf.dump_bmon_rebin:
hlr_utils.write_file(conf.output, "text/Spec", dbm_som4,
output_ext="bmrl",
extra_tag=dataset_type,
verbose=conf.verbose,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
message="beam monitor wavelength information "\
+"(rebinned)")
# Step 7: Normalize data by beam monitor
if not conf.no_bmon_norm:
if conf.verbose:
print "Normalizing data by beam monitor"
if t is not None:
t.getTime(False)
dp_som6 = common_lib.div_ncerr(dp_som5, dbm_som4)
if t is not None:
t.getTime(msg="After normalizing data by beam monitor ")
else:
dp_som6 = dp_som5
del dp_som5
if transmission:
return dp_som6
if conf.dump_wave_bmnorm:
dp_som6_1 = dr_lib.sum_by_rebin_frac(dp_som6,
conf.lambda_bins.toNessiList())
write_message = "combined pixel wavelength information"
write_message += " (beam monitor normalized)"
hlr_utils.write_file(conf.output, "text/Spec", dp_som6_1,
output_ext="pbml",
extra_tag=dataset_type,
verbose=conf.verbose,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
message=write_message)
del dp_som6_1
if conf.dump_wave_r:
dp_som6_1 = dr_lib.create_param_vs_Y(dp_som6, "radius", "param_array",
conf.r_bins.toNessiList(),
rebin_axis=conf.lambda_bins.toNessiList(),
y_label="counts",
y_units="counts / (Angstrom * m)",
x_labels=["Radius", "Wavelength"],
x_units=["m", "Angstrom"])
hlr_utils.write_file(conf.output, "text/Dave2d", dp_som6_1,
output_ext="lvr",
extra_tag=dataset_type,
verbose=conf.verbose,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
message="wavelength vs radius information")
del dp_som6_1
if conf.dump_wave_theta:
dp_som6_1 = dr_lib.create_param_vs_Y(dp_som6, "polar", "param_array",
conf.theta_bins.toNessiList(),
rebin_axis=conf.lambda_bins.toNessiList(),
y_label="counts",
y_units="counts / (Angstrom * rads)",
x_labels=["Polar Angle", "Wavelength"],
x_units=["rads", "Angstrom"])
hlr_utils.write_file(conf.output, "text/Dave2d", dp_som6_1,
output_ext="lvt",
extra_tag=dataset_type,
verbose=conf.verbose,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
message="wavelength vs polar angle information")
del dp_som6_1
# Step 8: Rebin transmission monitor axis onto detector pixel axis
if trans_data is not None:
print "Reading in transmission monitor data from file"
dtm_som3 = dr_lib.add_files([trans_data],
dataset_type=dataset_type,
dst_type="text/Spec",
Verbose=conf.verbose,
Timer=t)
if conf.verbose and dtm_som3 is not None:
print "Rebin transmission monitor axis to detector pixel axis"
if t is not None:
t.getTime(False)
dtm_som4 = dr_lib.rebin_monitor(dtm_som3, dp_som6, rtype="frac")
if t is not None and dtm_som3 is not None:
t.getTime(msg="After rebinning transmission monitor ")
del dtm_som3
# Step 9: Normalize data by transmission monitor
if conf.verbose and dtm_som4 is not None:
print "Normalizing data by transmission monitor"
if t is not None:
t.getTime(False)
if dtm_som4 is not None:
# The transmission spectra derived from sas_tranmission does not have
# the same y information by convention as sample data or a
# tranmission monitor. Therefore, we'll fake it by setting the
# y information from the sample data into the transmission
if trans_data is not None:
dtm_som4.setYLabel(dp_som6.getYLabel())
dtm_som4.setYUnits(dp_som6.getYUnits())
dp_som7 = common_lib.div_ncerr(dp_som6, dtm_som4)
else:
dp_som7 = dp_som6
if t is not None and dtm_som4 is not None:
t.getTime(msg="After normalizing data by transmission monitor ")
del dp_som6
# Step 10: Convert wavelength to Q for data
if conf.verbose:
print "Converting data from wavelength to scalar Q"
if t is not None:
t.getTime(False)
dp_som8 = common_lib.wavelength_to_scalar_Q(dp_som7)
if t is not None:
t.getTime(msg="After converting wavelength to scalar Q ")
del dp_som7
if conf.facility == "LENS":
# Step 11: Apply SAS correction factor to data
if conf.verbose:
print "Applying geometrical correction"
if t is not None:
t.getTime(False)
dp_som9 = dr_lib.apply_sas_correct(dp_som8)
if t is not None:
t.getTime(msg="After applying geometrical correction ")
return dp_som9
else:
return dp_som8
def process_dgs_data(obj, conf, bcan, ecan, tcoeff, **kwargs):
"""
This function combines Steps 7 through 16 in Section 2.1.1 of the data
reduction process for Direct Geometry Spectrometers as specified by the
document at
U{http://neutrons.ornl.gov/asg/projects/SCL/reqspec/DR_Lib_RS.doc}. The
function takes a calibrated dataset, a L{hlr_utils.Configure} object and
processes the data accordingly.
@param obj: A calibrated dataset object.
@type obj: C{SOM.SOM}
@param conf: Object that contains the current setup of the driver.
@type conf: L{hlr_utils.Configure}
@param bcan: The object containing the black can data.
@type bcan: C{SOM.SOM}
@param ecan: The object containing the empty can data.
@type ecan: C{SOM.SOM}
@param tcoeff: The transmission coefficient appropriate to the given data
set.
@type tcoeff: C{tuple}
@param kwargs: A list of keyword arguments that the function accepts:
@keyword dataset_type: The practical name of the dataset being processed.
The default value is I{data}.
@type dataset_type: C{string}
@keyword cwp_used: A flag signalling the use of the chopper phase
corrections.
@type cwp_used: C{bool}
@keyword timer: Timing object so the function can perform timing estimates.
@type timer: C{sns_timer.DiffTime}
@return: Object that has undergone all requested processing steps
@rtype: C{SOM.SOM}
"""
import array_manip
import common_lib
import dr_lib
import hlr_utils
# Check keywords
try:
dataset_type = kwargs["dataset_type"]
except KeyError:
dataset_type = "data"
try:
t = kwargs["timer"]
except KeyError:
t = None
cwp_used = kwargs.get("cwp_used", False)
if conf.verbose:
print "Processing %s information" % dataset_type
# Step 7: Create black can background contribution
if bcan is not None:
if conf.verbose:
print "Creating black can background contribution for %s" \
% dataset_type
if t is not None:
t.getTime(False)
bccoeff = array_manip.sub_ncerr(1.0, 0.0, tcoeff[0], tcoeff[1])
bcan1 = common_lib.mult_ncerr(bcan, bccoeff)
if t is not None:
t.getTime(msg="After creating black can background contribution ")
del bcan
else:
bcan1 = None
# Step 8: Create empty can background contribution
if ecan is not None:
if conf.verbose:
print "Creating empty can background contribution for %s" \
% dataset_type
if t is not None:
t.getTime(False)
ecan1 = common_lib.mult_ncerr(ecan, tcoeff)
if t is not None:
t.getTime(msg="After creating empty can background contribution ")
del ecan
else:
ecan1 = None
# Step 9: Create background spectra
if bcan1 is not None or ecan1 is not None and conf.verbose:
print "Creating background spectra for %s" % dataset_type
if bcan1 is not None and ecan1 is not None:
if cwp_used:
if conf.verbose:
print "Rebinning empty can to black can axis."
ecan2 = common_lib.rebin_axis_1D_frac(ecan1, bcan1[0].axis[0].val)
else:
ecan2 = ecan1
del ecan1
if t is not None:
t.getTime(False)
b_som = common_lib.add_ncerr(bcan1, ecan2)
if t is not None:
t.getTime(msg="After creating background spectra ")
elif bcan1 is not None and ecan1 is None:
b_som = bcan1
elif bcan1 is None and ecan1 is not None:
b_som = ecan1
else:
b_som = None
del bcan1, ecan1
if cwp_used:
if conf.verbose:
print "Rebinning background spectra to %s" % dataset_type
b_som1 = common_lib.rebin_axis_1D_frac(b_som, obj[0].axis[0].val)
else:
b_som1 = b_som
del b_som
if conf.dump_ctof_comb and b_som1 is not None:
b_som_1 = dr_lib.sum_all_spectra(b_som1)
hlr_utils.write_file(conf.output, "text/Spec", b_som_1,
output_ext="ctof",
extra_tag="background",
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
verbose=conf.verbose,
message="combined background TOF information")
del b_som_1
# Step 10: Subtract background from data
obj1 = dr_lib.subtract_bkg_from_data(obj, b_som1, verbose=conf.verbose,
timer=t,
dataset1=dataset_type,
dataset2="background")
del obj, b_som1
# Step 11: Calculate initial velocity
if conf.verbose:
print "Calculating initial velocity"
if t is not None:
t.getTime(False)
if conf.initial_energy is not None:
initial_wavelength = common_lib.energy_to_wavelength(\
conf.initial_energy.toValErrTuple())
initial_velocity = common_lib.wavelength_to_velocity(\
initial_wavelength)
else:
# This should actually calculate it, but don't have a way right now
pass
if t is not None:
t.getTime(msg="After calculating initial velocity ")
# Step 12: Calculate the time-zero offset
if conf.time_zero_offset is not None:
time_zero_offset = conf.time_zero_offset.toValErrTuple()
else:
# This should actually calculate it, but don't have a way right now
time_zero_offset = (0.0, 0.0)
# Step 13: Convert time-of-flight to final velocity
if conf.verbose:
print "Converting TOF to final velocity DGS"
if t is not None:
t.getTime(False)
obj2 = common_lib.tof_to_final_velocity_dgs(obj1, initial_velocity,
time_zero_offset,
units="microsecond")
if t is not None:
t.getTime(msg="After calculating TOF to final velocity DGS ")
del obj1
# Step 14: Convert final velocity to final wavelength
if conf.verbose:
print "Converting final velocity DGS to final wavelength"
if t is not None:
t.getTime(False)
obj3 = common_lib.velocity_to_wavelength(obj2)
if t is not None:
t.getTime(msg="After calculating velocity to wavelength ")
del obj2
if conf.dump_wave_comb:
obj3_1 = dr_lib.sum_all_spectra(obj3,
rebin_axis=conf.lambda_bins.toNessiList())
hlr_utils.write_file(conf.output, "text/Spec", obj3_1,
output_ext="fwv",
extra_tag=dataset_type,
data_ext=conf.ext_replacement,
path_replacement=conf.path_replacement,
verbose=conf.verbose,
message="combined final wavelength information")
del obj3_1
# Step 15: Create the detector efficiency
if conf.det_eff is not None:
if conf.verbose:
print "Creating detector efficiency spectra"
if t is not None:
t.getTime(False)
det_eff = dr_lib.create_det_eff(obj3)
if t is not None:
t.getTime(msg="After creating detector efficiency spectra ")
else:
det_eff = None
# Step 16: Divide the detector pixel spectra by the detector efficiency
if det_eff is not None:
if conf.verbose:
print "Correcting %s for detector efficiency" % dataset_type
if t is not None:
t.getTime(False)
obj4 = common_lib.div_ncerr(obj3, det_eff)
if t is not None:
t.getTime(msg="After correcting %s for detector efficiency" \
% dataset_type)
else:
obj4 = obj3
del obj3, det_eff
return obj4
