Exemplo n.º 1
0
def process_reflp_data(datalist,
                       conf,
                       roi_file,
                       bkg_roi_file=None,
                       no_bkg=False,
                       **kwargs):
    """
    This function combines Steps 1 through 3 in section 2.4.6.1 of the data
    reduction process for Reduction from TOF to lambda_T as specified by
    the document 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,
    region-of-interest (ROI) file for the normalization dataset, a background
    region-of-interest (ROI) file and an optional flag about background
    subtractionand processes the data accordingly.

    @param datalist: 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 roi_file: The file containing the list of pixel IDs for the region
                     of interest. This only applies to normalization data. 
    @type roi_file: C{string}

    @param bkg_roi_file: The file containing the list of pixel IDs for the
                         (possible) background region of interest.
    @type bkg_roi_file: C{string}    
    
    @param no_bkg: (OPTIONAL) Flag which determines if the background will be
                              calculated and subtracted.
    @type no_bkg: C{boolean}    

    @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 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 hlr_utils
    import common_lib
    import dr_lib

    # Check keywords
    try:
        i_geom_dst = kwargs["inst_geom_dst"]
    except KeyError:
        i_geom_dst = None

    try:
        t = kwargs["timer"]
    except KeyError:
        t = None

    if roi_file is not None:
        # Normalization
        dataset_type = "norm"
    else:
        # Sample data
        dataset_type = "data"

    so_axis = "time_of_flight"

    # Step 0: Open data files and select ROI (if necessary)
    if conf.verbose:
        print "Reading %s file" % dataset_type

    if len(conf.norm_data_paths) and dataset_type == "norm":
        data_path = conf.norm_data_paths.toPath()
    else:
        data_path = conf.data_paths.toPath()

    (d_som1, b_som1) = dr_lib.add_files_bg(datalist,
                                           Data_Paths=data_path,
                                           SO_Axis=so_axis,
                                           dataset_type=dataset_type,
                                           Signal_ROI=roi_file,
                                           Bkg_ROI=bkg_roi_file,
                                           Verbose=conf.verbose,
                                           Timer=t)

    if t is not None:
        t.getTime(msg="After reading %s " % dataset_type)

    # Override geometry if necessary
    if i_geom_dst is not None:
        i_geom_dst.setGeometry(conf.data_paths.toPath(), d_som1)

    if dataset_type == "data":
        # Get TOF bin width
        conf.delta_TOF = d_som1[0].axis[0].val[1] - d_som1[0].axis[0].val[0]

    if conf.mon_norm:
        if conf.verbose:
            print "Reading in monitor data from %s file" % dataset_type

        # The [0] is to get the data SOM and ignore the None background SOM
        dm_som1 = dr_lib.add_files(datalist,
                                   Data_Paths=conf.mon_path.toPath(),
                                   SO_Axis=so_axis,
                                   dataset_type=dataset_type,
                                   Verbose=conf.verbose,
                                   Timer=t)

        if t is not None:
            t.getTime(msg="After reading monitor data ")

    else:
        dm_som1 = None

    # Step 1: Sum all spectra along the low resolution direction
    # Set sorting for REF_L
    if conf.verbose:
        print "Summing over low resolution direction"

    # Set sorting
    (y_sort, cent_pixel) = hlr_utils.get_ref_integration_direction(
        conf.int_dir, conf.inst, d_som1.attr_list.instrument)

    if t is not None:
        t.getTime(False)

    d_som2 = dr_lib.sum_all_spectra(d_som1,
                                    y_sort=y_sort,
                                    stripe=True,
                                    pixel_fix=cent_pixel)

    if b_som1 is not None:
        b_som2 = dr_lib.sum_all_spectra(b_som1,
                                        y_sort=y_sort,
                                        stripe=True,
                                        pixel_fix=cent_pixel)
        del b_som1
    else:
        b_som2 = b_som1

    if t is not None:
        t.getTime(msg="After summing low resolution direction ")

    del d_som1

    # Determine background spectrum
    if conf.verbose and not no_bkg:
        print "Determining %s background" % dataset_type

    if b_som2 is not None:
        B = dr_lib.calculate_ref_background(b_som2,
                                            no_bkg,
                                            conf.inst,
                                            None,
                                            aobj=d_som2)
    if t is not None:
        t.getTime(msg="After background determination")

    # Subtract background spectrum from data spectra
    if not no_bkg:
        d_som3 = dr_lib.subtract_bkg_from_data(d_som2,
                                               B,
                                               verbose=conf.verbose,
                                               timer=t,
                                               dataset1="data",
                                               dataset2="background")
    else:
        d_som3 = d_som2

    del d_som2

    # Zero the spectra if necessary
    if roi_file is None and (conf.tof_cut_min is not None or \
                             conf.tof_cut_max is not None):
        import utils
        # Find the indicies for the non zero range
        if conf.tof_cut_min is None:
            conf.TOF_min = d_som3[0].axis[0].val[0]
            start_index = 0
        else:
            start_index = utils.bisect_helper(d_som3[0].axis[0].val,
                                              conf.tof_cut_min)

        if conf.tof_cut_max is None:
            conf.TOF_max = d_som3[0].axis[0].val[-1]
            end_index = len(d_som3[0].axis[0].val) - 1
        else:
            end_index = utils.bisect_helper(d_som3[0].axis[0].val,
                                            conf.tof_cut_max)

        nz_list = []
        for i in xrange(hlr_utils.get_length(d_som3)):
            nz_list.append((start_index, end_index))

        d_som4 = dr_lib.zero_spectra(d_som3, nz_list, use_bin_index=True)
    else:
        conf.TOF_min = d_som3[0].axis[0].val[0]
        conf.TOF_max = d_som3[0].axis[0].val[-1]
        d_som4 = d_som3

    del d_som3

    # Step N: Convert TOF to wavelength
    if conf.verbose:
        print "Converting TOF to wavelength"

    if t is not None:
        t.getTime(False)

    d_som5 = common_lib.tof_to_wavelength(d_som4,
                                          inst_param="total",
                                          units="microsecond")
    if dm_som1 is not None:
        dm_som2 = common_lib.tof_to_wavelength(dm_som1, units="microsecond")
    else:
        dm_som2 = None

    del dm_som1

    if t is not None:
        t.getTime(msg="After converting TOF to wavelength ")

    del d_som4

    if conf.mon_norm:
        dm_som3 = dr_lib.rebin_monitor(dm_som2, d_som5, rtype="frac")
    else:
        dm_som3 = None

    del dm_som2

    if not conf.mon_norm:
        # Step 2: Multiply the spectra by the proton charge
        if conf.verbose:
            print "Multiply spectra by proton charge"

        pc_tag = dataset_type + "-proton_charge"
        proton_charge = d_som5.attr_list[pc_tag]

        if t is not None:
            t.getTime(False)

        d_som6 = common_lib.div_ncerr(d_som5, (proton_charge.getValue(), 0.0))

        if t is not None:
            t.getTime(msg="After scaling by proton charge ")
    else:
        if conf.verbose:
            print "Normalize by monitor spectrum"

        if t is not None:
            t.getTime(False)

        d_som6 = common_lib.div_ncerr(d_som5, dm_som3)

        if t is not None:
            t.getTime(msg="After monitor normalization ")

    del d_som5, dm_som3

    if roi_file is None:
        return d_som6
    else:
        # Step 3: Make one spectrum for normalization dataset
        # Need to create a final rebinning axis
        pathlength = d_som6.attr_list.instrument.get_total_path(
            det_secondary=True)

        delta_lambda = common_lib.tof_to_wavelength((conf.delta_TOF, 0.0),
                                                    pathlength=pathlength)

        lambda_bins = dr_lib.create_axis_from_data(d_som6,
                                                   width=delta_lambda[0])

        return dr_lib.sum_by_rebin_frac(d_som6, lambda_bins.toNessiList())
Exemplo n.º 2
0
def run(config, tim):
    """
    This method is where the data reduction process gets done.

    @param config: Object containing the data reduction configuration
                   information.
    @type config: L{hlr_utils.Configure}

    @param tim: Object that will allow the method to perform timing
                evaluations.
    @type tim: C{sns_time.DiffTime}
    """
    import array_manip
    import common_lib
    import dr_lib
    import DST
    import SOM

    import math

    if tim is not None:
        tim.getTime(False)
        old_time = tim.getOldTime()

    if config.data is None:
        raise RuntimeError("Need to pass a data filename to the driver "\
                           +"script.")

    # Read in sample data geometry if one is provided
    if config.data_inst_geom is not None:
        if config.verbose:
            print "Reading in sample data instrument geometry file"

        data_inst_geom_dst = DST.getInstance("application/x-NxsGeom",
                                             config.data_inst_geom)
    else:
        data_inst_geom_dst = None

    # Read in normalization data geometry if one is provided
    if config.norm_inst_geom is not None:
        if config.verbose:
            print "Reading in normalization instrument geometry file"
            
        norm_inst_geom_dst = DST.getInstance("application/x-NxsGeom",
                                             config.norm_inst_geom)
    else:
        norm_inst_geom_dst = None        
    
    # Perform Steps 1-2 on sample data
    d_som1 = dr_lib.process_reflp_data(config.data, config, None,
                                       config.dbkg_roi_file,
                                       config.no_bkg,
                                       inst_geom_dst=data_inst_geom_dst,
                                       timer=tim)

    # Get the detector angle
    if config.omega is None:
        # Make a fake SO
        so = SOM.SO()
        try: 
            theta = hlr_utils.get_special(d_som1.attr_list["Theta"], so)
        except KeyError: 
            theta = (float('nan'), float('nan'))
    else:
        theta = config.omega.toFullTuple()
        
    if theta[0] is not None: 
        if theta[2] == "degrees" or theta[2] == "degree": 
            theta_rads = (theta[0] * (math.pi / 180.0), 0.0)
        else: 
            theta_rads = (theta[0], 0.0)
    else: 
        theta_rads = (float('nan'), float('nan'))

    d_som1.attr_list["data-theta"] = (theta_rads[0], theta_rads[1], "radians")

    # Perform Steps 1-3 on normalization data
    if config.norm is not None:
        n_som1 = dr_lib.process_reflp_data(config.norm, config,
                                           config.norm_roi_file,
                                           config.nbkg_roi_file,
                                           config.no_norm_bkg,
                                           inst_geom_dst=norm_inst_geom_dst,
                                           timer=tim)
    else:
        n_som1 = None

    # Closing sample data instrument geometry file
    if data_inst_geom_dst is not None:
        data_inst_geom_dst.release_resource()

    # Closing normalization data instrument geometry file
    if norm_inst_geom_dst is not None:
        norm_inst_geom_dst.release_resource()        

    # Step 4: Divide data by normalization
    if config.verbose and config.norm is not None:
        print "Scale data by normalization"

    if tim is not None:
        tim.getTime(False)

    if config.norm is not None:
        # Need to rebin the normalization spectra to the data pixel spectra
        n_som2 = dr_lib.rebin_monitor(n_som1, d_som1, rtype="frac")
        # Now divide the spectra
        d_som2 = common_lib.div_ncerr(d_som1, n_som2)
        del n_som2
    else:
        d_som2 = d_som1

    if tim is not None and config.norm is not None:
        tim.getTime(msg="After normalizing signal spectra")

    del d_som1, n_som1

    sin_theta_rads = (math.sin(theta_rads[0]), math.sin(theta_rads[1]))
    if sin_theta_rads[0] < 0.0:
        sin_theta_rads = (math.fabs(sin_theta_rads[0]),
                          math.fabs(sin_theta_rads[1]))

    # Step 6: Scale wavelength axis by sin(theta) to make lambda_T
    if config.verbose:
        print "Scaling wavelength axis by sin(theta)"
    
    if tim is not None:
        tim.getTime(False)
        
    d_som3 = common_lib.div_ncerr(d_som2, sin_theta_rads, axis="x")

    if tim is not None:
        tim.getTime(msg="After scaling wavelength axis ")

    del d_som2

    d_som3.setAxisLabel(0, "lambda_T")

    # Step 7: Rebin to lambda_T axis
    if config.verbose:
        print "Rebinning spectra"

    if config.lambdap_bins is None:
        # Create a binning scheme
        pathlength = d_som3.attr_list.instrument.get_total_path(
            det_secondary=True)

        delta_lambda = common_lib.tof_to_wavelength((config.delta_TOF, 0.0),
                                                    pathlength=pathlength)
 
        delta_lambdap = array_manip.div_ncerr(delta_lambda[0], delta_lambda[1],
                                              sin_theta_rads[0], 0.0)

        config.lambdap_bins = dr_lib.create_axis_from_data(d_som3,
                                                       width=delta_lambdap[0])
    else:
        # Do nothing, got the binning scheme
        pass

    if tim is not None:
        tim.getTime(False)

    d_som4 = common_lib.rebin_axis_1D_frac(d_som3,
                                           config.lambdap_bins.toNessiList())

    if tim is not None:
        tim.getTime(msg="After rebinning spectra ")

    del d_som3

    if config.inst == "REF_M":
        # Clean up spectrum
        if config.tof_cut_min is not None:
            tof_cut_min = float(config.tof_cut_min)
        else:
            tof_cut_min = config.TOF_min

        if config.tof_cut_max is not None:
            tof_cut_max = float(config.tof_cut_max)
        else:
            tof_cut_max = config.TOF_max

        pathlength = d_som4.attr_list.instrument.get_total_path(
            det_secondary=True)

        lambda_min = common_lib.tof_to_wavelength((tof_cut_min, 0.0),
                                                  pathlength=pathlength)

        lambda_T_min = common_lib.div_ncerr(lambda_min, sin_theta_rads)
        
        lambda_max = common_lib.tof_to_wavelength((tof_cut_max, 0.0),
                                                  pathlength=pathlength)

        lambda_T_max = common_lib.div_ncerr(lambda_max, sin_theta_rads)

        nz_list = []
        for i in xrange(hlr_utils.get_length(d_som4)):
            nz_list.append((lambda_T_min[0], lambda_T_max[0]))
        
        d_som4A = dr_lib.zero_spectra(d_som4, nz_list)
    else:
        d_som4A = d_som4

    del d_som4

    # Step 8: Write out all spectra to a file
    hlr_utils.write_file(config.output, "text/Spec", d_som4A,
                         replace_ext=False,
                         replace_path=False,
                         verbose=config.verbose,
                         message="Reflectivity information")

    if config.dump_twod:
        d_som5 = dr_lib.create_X_vs_pixpos(d_som4A,
                                           config.lambdap_bins.toNessiList(),
                                           rebin=False,
                                           y_label="R",
                                           y_units="",
                                           x_label="$\lambda_T$",
                                           x_units="$\AA$")

        hlr_utils.write_file(config.output, "text/Dave2d", d_som5,
                             output_ext="plp", verbose=config.verbose,
                             data_ext=config.ext_replacement,
                             path_replacement=config.path_replacement,
                             message="2D Reflectivity information")

    d_som4A.attr_list["config"] = config

    hlr_utils.write_file(config.output, "text/rmd", d_som4A,
                         output_ext="rmd", verbose=config.verbose,
                         data_ext=config.ext_replacement,
                         path_replacement=config.path_replacement,
                         message="metadata")

    if tim is not None:
        tim.setOldTime(old_time)
        tim.getTime(msg="Total Running Time")    
Exemplo n.º 3
0
def run(config, tim):
    """
    This method is where the data reduction process gets done.

    @param config: Object containing the data reduction configuration
                   information.
    @type config: L{hlr_utils.Configure}

    @param tim: Object that will allow the method to perform timing
                evaluations.
    @type tim: C{sns_time.DiffTime}
    """
    import array_manip
    import common_lib
    import dr_lib
    import DST
    import SOM

    import math

    if tim is not None:
        tim.getTime(False)
        old_time = tim.getOldTime()

    if config.data is None:
        raise RuntimeError("Need to pass a data filename to the driver "\
                           +"script.")

    # Read in sample data geometry if one is provided
    if config.data_inst_geom is not None:
        if config.verbose:
            print "Reading in sample data instrument geometry file"

        data_inst_geom_dst = DST.getInstance("application/x-NxsGeom",
                                             config.data_inst_geom)
    else:
        data_inst_geom_dst = None

    # Read in normalization data geometry if one is provided
    if config.norm_inst_geom is not None:
        if config.verbose:
            print "Reading in normalization instrument geometry file"

        norm_inst_geom_dst = DST.getInstance("application/x-NxsGeom",
                                             config.norm_inst_geom)
    else:
        norm_inst_geom_dst = None

    # Perform Steps 1-2 on sample data
    d_som1 = dr_lib.process_reflp_data(config.data,
                                       config,
                                       None,
                                       config.dbkg_roi_file,
                                       config.no_bkg,
                                       inst_geom_dst=data_inst_geom_dst,
                                       timer=tim)

    # Get the detector angle
    if config.omega is None:
        # Make a fake SO
        so = SOM.SO()
        try:
            theta = hlr_utils.get_special(d_som1.attr_list["Theta"], so)
        except KeyError:
            theta = (float('nan'), float('nan'))
    else:
        theta = config.omega.toFullTuple()

    if theta[0] is not None:
        if theta[2] == "degrees" or theta[2] == "degree":
            theta_rads = (theta[0] * (math.pi / 180.0), 0.0)
        else:
            theta_rads = (theta[0], 0.0)
    else:
        theta_rads = (float('nan'), float('nan'))

    d_som1.attr_list["data-theta"] = (theta_rads[0], theta_rads[1], "radians")

    # Perform Steps 1-3 on normalization data
    if config.norm is not None:
        n_som1 = dr_lib.process_reflp_data(config.norm,
                                           config,
                                           config.norm_roi_file,
                                           config.nbkg_roi_file,
                                           config.no_norm_bkg,
                                           inst_geom_dst=norm_inst_geom_dst,
                                           timer=tim)
    else:
        n_som1 = None

    # Closing sample data instrument geometry file
    if data_inst_geom_dst is not None:
        data_inst_geom_dst.release_resource()

    # Closing normalization data instrument geometry file
    if norm_inst_geom_dst is not None:
        norm_inst_geom_dst.release_resource()

    # Step 4: Divide data by normalization
    if config.verbose and config.norm is not None:
        print "Scale data by normalization"

    if tim is not None:
        tim.getTime(False)

    if config.norm is not None:
        # Need to rebin the normalization spectra to the data pixel spectra
        n_som2 = dr_lib.rebin_monitor(n_som1, d_som1, rtype="frac")
        # Now divide the spectra
        d_som2 = common_lib.div_ncerr(d_som1, n_som2)
        del n_som2
    else:
        d_som2 = d_som1

    if tim is not None and config.norm is not None:
        tim.getTime(msg="After normalizing signal spectra")

    del d_som1, n_som1

    sin_theta_rads = (math.sin(theta_rads[0]), math.sin(theta_rads[1]))
    if sin_theta_rads[0] < 0.0:
        sin_theta_rads = (math.fabs(sin_theta_rads[0]),
                          math.fabs(sin_theta_rads[1]))

    # Step 6: Scale wavelength axis by sin(theta) to make lambda_T
    if config.verbose:
        print "Scaling wavelength axis by sin(theta)"

    if tim is not None:
        tim.getTime(False)

    d_som3 = common_lib.div_ncerr(d_som2, sin_theta_rads, axis="x")

    if tim is not None:
        tim.getTime(msg="After scaling wavelength axis ")

    del d_som2

    d_som3.setAxisLabel(0, "lambda_T")

    # Step 7: Rebin to lambda_T axis
    if config.verbose:
        print "Rebinning spectra"

    if config.lambdap_bins is None:
        # Create a binning scheme
        pathlength = d_som3.attr_list.instrument.get_total_path(
            det_secondary=True)

        delta_lambda = common_lib.tof_to_wavelength((config.delta_TOF, 0.0),
                                                    pathlength=pathlength)

        delta_lambdap = array_manip.div_ncerr(delta_lambda[0], delta_lambda[1],
                                              sin_theta_rads[0], 0.0)

        config.lambdap_bins = dr_lib.create_axis_from_data(
            d_som3, width=delta_lambdap[0])
    else:
        # Do nothing, got the binning scheme
        pass

    if tim is not None:
        tim.getTime(False)

    d_som4 = common_lib.rebin_axis_1D_frac(d_som3,
                                           config.lambdap_bins.toNessiList())

    if tim is not None:
        tim.getTime(msg="After rebinning spectra ")

    del d_som3

    if config.inst == "REF_M":
        # Clean up spectrum
        if config.tof_cut_min is not None:
            tof_cut_min = float(config.tof_cut_min)
        else:
            tof_cut_min = config.TOF_min

        if config.tof_cut_max is not None:
            tof_cut_max = float(config.tof_cut_max)
        else:
            tof_cut_max = config.TOF_max

        pathlength = d_som4.attr_list.instrument.get_total_path(
            det_secondary=True)

        lambda_min = common_lib.tof_to_wavelength((tof_cut_min, 0.0),
                                                  pathlength=pathlength)

        lambda_T_min = common_lib.div_ncerr(lambda_min, sin_theta_rads)

        lambda_max = common_lib.tof_to_wavelength((tof_cut_max, 0.0),
                                                  pathlength=pathlength)

        lambda_T_max = common_lib.div_ncerr(lambda_max, sin_theta_rads)

        nz_list = []
        for i in xrange(hlr_utils.get_length(d_som4)):
            nz_list.append((lambda_T_min[0], lambda_T_max[0]))

        d_som4A = dr_lib.zero_spectra(d_som4, nz_list)
    else:
        d_som4A = d_som4

    del d_som4

    # Step 8: Write out all spectra to a file
    hlr_utils.write_file(config.output,
                         "text/Spec",
                         d_som4A,
                         replace_ext=False,
                         replace_path=False,
                         verbose=config.verbose,
                         message="Reflectivity information")

    if config.dump_twod:
        d_som5 = dr_lib.create_X_vs_pixpos(d_som4A,
                                           config.lambdap_bins.toNessiList(),
                                           rebin=False,
                                           y_label="R",
                                           y_units="",
                                           x_label="$\lambda_T$",
                                           x_units="$\AA$")

        hlr_utils.write_file(config.output,
                             "text/Dave2d",
                             d_som5,
                             output_ext="plp",
                             verbose=config.verbose,
                             data_ext=config.ext_replacement,
                             path_replacement=config.path_replacement,
                             message="2D Reflectivity information")

    d_som4A.attr_list["config"] = config

    hlr_utils.write_file(config.output,
                         "text/rmd",
                         d_som4A,
                         output_ext="rmd",
                         verbose=config.verbose,
                         data_ext=config.ext_replacement,
                         path_replacement=config.path_replacement,
                         message="metadata")

    if tim is not None:
        tim.setOldTime(old_time)
        tim.getTime(msg="Total Running Time")
Exemplo n.º 4
0
def process_reflp_data(datalist, conf, roi_file, bkg_roi_file=None,
                     no_bkg=False, **kwargs):
    """
    This function combines Steps 1 through 3 in section 2.4.6.1 of the data
    reduction process for Reduction from TOF to lambda_T as specified by
    the document 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,
    region-of-interest (ROI) file for the normalization dataset, a background
    region-of-interest (ROI) file and an optional flag about background
    subtractionand processes the data accordingly.

    @param datalist: 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 roi_file: The file containing the list of pixel IDs for the region
                     of interest. This only applies to normalization data. 
    @type roi_file: C{string}

    @param bkg_roi_file: The file containing the list of pixel IDs for the
                         (possible) background region of interest.
    @type bkg_roi_file: C{string}    
    
    @param no_bkg: (OPTIONAL) Flag which determines if the background will be
                              calculated and subtracted.
    @type no_bkg: C{boolean}    

    @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 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 hlr_utils
    import common_lib
    import dr_lib

    # Check keywords
    try:
        i_geom_dst = kwargs["inst_geom_dst"]
    except KeyError:
        i_geom_dst = None
    
    try:
        t = kwargs["timer"]
    except KeyError:
        t = None

    if roi_file is not None:
        # Normalization
        dataset_type = "norm"
    else:
        # Sample data
        dataset_type = "data"

    so_axis = "time_of_flight"

    # Step 0: Open data files and select ROI (if necessary)
    if conf.verbose:
        print "Reading %s file" % dataset_type

    if len(conf.norm_data_paths) and dataset_type == "norm":
        data_path = conf.norm_data_paths.toPath()
    else:
        data_path = conf.data_paths.toPath()

    (d_som1, b_som1) = dr_lib.add_files_bg(datalist,
                                           Data_Paths=data_path,
                                           SO_Axis=so_axis,
                                           dataset_type=dataset_type,
                                           Signal_ROI=roi_file,
                                           Bkg_ROI=bkg_roi_file,
                                           Verbose=conf.verbose,
                                           Timer=t)

    if t is not None:
        t.getTime(msg="After reading %s " % dataset_type)

    # Override geometry if necessary
    if i_geom_dst is not None:
        i_geom_dst.setGeometry(conf.data_paths.toPath(), d_som1)

    if dataset_type == "data":
        # Get TOF bin width
        conf.delta_TOF = d_som1[0].axis[0].val[1] - d_som1[0].axis[0].val[0]

    if conf.mon_norm:
        if conf.verbose:
            print "Reading in monitor data from %s file" % dataset_type

        # The [0] is to get the data SOM and ignore the None background SOM
        dm_som1 = dr_lib.add_files(datalist, Data_Paths=conf.mon_path.toPath(),
                                   SO_Axis=so_axis,
                                   dataset_type=dataset_type,
                                   Verbose=conf.verbose,
                                   Timer=t)
        
        if t is not None:
            t.getTime(msg="After reading monitor data ")
            
    else:
        dm_som1 = None

    # Step 1: Sum all spectra along the low resolution direction
    # Set sorting for REF_L
    if conf.verbose:
        print "Summing over low resolution direction"

    # Set sorting
    (y_sort,
     cent_pixel) = hlr_utils.get_ref_integration_direction(conf.int_dir,
                                                           conf.inst,
                                                  d_som1.attr_list.instrument)
    
    if t is not None:
        t.getTime(False)

    d_som2 = dr_lib.sum_all_spectra(d_som1, y_sort=y_sort, stripe=True,
                                    pixel_fix=cent_pixel)

    if b_som1 is not None:
        b_som2 = dr_lib.sum_all_spectra(b_som1, y_sort=y_sort, stripe=True,
                                        pixel_fix=cent_pixel)
        del b_som1
    else:
        b_som2 = b_som1

    if t is not None:
        t.getTime(msg="After summing low resolution direction ")
        
    del d_som1

    # Determine background spectrum
    if conf.verbose and not no_bkg:
        print "Determining %s background" % dataset_type

    if b_som2 is not None:
        B = dr_lib.calculate_ref_background(b_som2, no_bkg, conf.inst, None,
                                            aobj=d_som2)
    if t is not None:
        t.getTime(msg="After background determination")

    # Subtract background spectrum from data spectra
    if not no_bkg:
        d_som3 = dr_lib.subtract_bkg_from_data(d_som2, B,
                                               verbose=conf.verbose,
                                               timer=t,
                                               dataset1="data",
                                               dataset2="background")
    else:
        d_som3 = d_som2

    del d_som2

    # Zero the spectra if necessary
    if roi_file is None and (conf.tof_cut_min is not None or \
                             conf.tof_cut_max is not None):
        import utils
        # Find the indicies for the non zero range
        if conf.tof_cut_min is None:
            conf.TOF_min = d_som3[0].axis[0].val[0]
            start_index = 0
        else:
            start_index = utils.bisect_helper(d_som3[0].axis[0].val,
                                              conf.tof_cut_min)

        if conf.tof_cut_max is None:
            conf.TOF_max = d_som3[0].axis[0].val[-1]
            end_index = len(d_som3[0].axis[0].val) - 1
        else:
            end_index = utils.bisect_helper(d_som3[0].axis[0].val,
                                            conf.tof_cut_max)

        nz_list = []
        for i in xrange(hlr_utils.get_length(d_som3)):
            nz_list.append((start_index, end_index))
        
        d_som4 = dr_lib.zero_spectra(d_som3, nz_list, use_bin_index=True)
    else:
        conf.TOF_min = d_som3[0].axis[0].val[0]
        conf.TOF_max = d_som3[0].axis[0].val[-1]
        d_som4 = d_som3

    del d_som3

    # Step N: Convert TOF to wavelength
    if conf.verbose:
        print "Converting TOF to wavelength"

    if t is not None:
        t.getTime(False)

    d_som5 = common_lib.tof_to_wavelength(d_som4, inst_param="total",
                                          units="microsecond")
    if dm_som1 is not None:
        dm_som2 = common_lib.tof_to_wavelength(dm_som1, units="microsecond")
    else:
        dm_som2 = None

    del dm_som1

    if t is not None:
        t.getTime(msg="After converting TOF to wavelength ")

    del d_som4

    if conf.mon_norm:
        dm_som3 = dr_lib.rebin_monitor(dm_som2, d_som5, rtype="frac")
    else:
        dm_som3 = None

    del dm_som2

    if not conf.mon_norm:
        # Step 2: Multiply the spectra by the proton charge
        if conf.verbose:
            print "Multiply spectra by proton charge"

        pc_tag = dataset_type + "-proton_charge"
        proton_charge = d_som5.attr_list[pc_tag]

        if t is not None:
            t.getTime(False)

        d_som6 = common_lib.div_ncerr(d_som5, (proton_charge.getValue(), 0.0))

        if t is not None:
            t.getTime(msg="After scaling by proton charge ")
    else:
        if conf.verbose:
            print "Normalize by monitor spectrum"

        if t is not None:
            t.getTime(False)

        d_som6 = common_lib.div_ncerr(d_som5, dm_som3)

        if t is not None:
            t.getTime(msg="After monitor normalization ")

    del d_som5, dm_som3

    if roi_file is None:
        return d_som6
    else:
        # Step 3: Make one spectrum for normalization dataset
        # Need to create a final rebinning axis
        pathlength = d_som6.attr_list.instrument.get_total_path(
            det_secondary=True)
        
        delta_lambda = common_lib.tof_to_wavelength((conf.delta_TOF, 0.0),
                                                    pathlength=pathlength)

        lambda_bins = dr_lib.create_axis_from_data(d_som6,
                                                   width=delta_lambda[0])

        return dr_lib.sum_by_rebin_frac(d_som6, lambda_bins.toNessiList())