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from django.core.urlresolvers import reverse

from model_utils.managers import InheritanceManager

from django.contrib.auth.models import User as DjangoUser


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import datetime
import thread
import string
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import os
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import glue
import glue.ligolw
import glue.ligolw.utils
import glue.ligolw.table
import glue.ligolw.lsctables
from glue.lal import LIGOTimeGPS

# XXX ER2.utils.  utils is in project directory.  ugh.
from utils import posixToGpsTime

from django.conf import settings
import pytz, time

SERVER_TZ = pytz.timezone(settings.TIME_ZONE)

# Let's say we start here on schema versions
#
# 1.0 -> 1.1   changed EventLog.comment from CharField(length=200) -> TextField
#
schema_version = "1.1"
#class User(models.Model):
    #name = models.CharField(max_length=100)
    #email = models.EmailField()
    #principal = models.CharField(max_length=100)
    #dn = models.CharField(max_length=100)
    #unixid = models.CharField(max_length=25)
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    #class Meta:
        #ordering = ["name"]
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    #def __unicode__(self):
        #return self.name
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class Group(models.Model):
    name = models.CharField(max_length=20)
    def __unicode__(self):
        return self.name

class Label(models.Model):
    name = models.CharField(max_length=20, unique=True)
    # XXX really, does this belong here? probably not.
    defaultColor = models.CharField(max_length=20, unique=False, default="black")
    def __unicode__(self):
        return self.name
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class Event(models.Model):

    objects = InheritanceManager() # Queries can return subclasses, if available.

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    ANALYSIS_TYPE_CHOICES = (
        ("LM",  "LowMass"),
        ("HM",  "HighMass"),
        ("GRB", "GRB"),
        ("RD",  "Ringdown"),
        ("OM",  "Omega"),
        ("Q",   "Q"),
        ("X",   "X"),
        ("CWB", "CWB"),
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        ("MBTA", "MBTAOnline"),
        ("HWINJ", "HardwareInjection"),
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    )
    DEFAULT_EVENT_NEIGHBORHOOD = (-5,5)
    submitter = models.ForeignKey(DjangoUser)
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    created = models.DateTimeField(auto_now_add=True)
    group = models.ForeignKey(Group)
    uid = models.CharField(max_length=20, default="")  # XXX deprecated.  should be removed.
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    analysisType = models.CharField(max_length=20, choices=ANALYSIS_TYPE_CHOICES)
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    instruments = models.CharField(max_length=20, default="")
    nevents = models.PositiveIntegerField(null=True)
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    far = models.FloatField(null=True)
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    likelihood = models.FloatField(null=True)

    # NOT from coinc_event, but so, so common.
    #   Note that the semantics for this is different depending
    #   on search type, so in some sense, querying on this may
    #   be considered, umm, wrong?  But it is a starting point.
    gpstime = models.PositiveIntegerField(null=True)
    labels = models.ManyToManyField(Label, through="Labelling")

    class Meta:
        ordering = ["-id"]

        if self.group.name == "Test":
            return "T%04d" % self.id
        elif self.analysisType == "HWINJ":
            return "H%04d" % self.id
        elif self.analysisType == "GRB":
            return "E%04d" % self.id
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    def weburl(self):
        # XXX Not good.  But then, it never was.
        return reverse('file_list', args=[self.graceid()])
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    # XXX This should be considered deprecated. (Branson, July 22, 2014.)
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    def clusterurl(self):
        #return "pcdev1.phys.uwm.edu:/archive/gracedb/data/%s" % self.graceid()
        return "file://pcdev1.phys.uwm.edu/archive/gracedb/data/%s" % self.graceid()
    def datadir(self, general=False):
        # Move to this.  Not the (more) ad hoc crap that's floating around.
        if general:
            subdir = "general"
        else:
            subdir = "private"
        return os.path.join(settings.GRACEDB_DATA_DIR, self.graceid(), subdir)
    def ligoApproved(self):
        return self.approval_set.filter(approvingCollaboration='L').count()

    def virgoApproved(self):
        return self.approval_set.filter(approvingCollaboration='V').count()
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    def reportingLatency(self):
        if self.gpstime:
            dt = self.created
            if not dt.tzinfo:
                dt = SERVER_TZ.localize(dt)
            posix_time = time.mktime(dt.timetuple())
            gps_time = int(posixToGpsTime(posix_time))
            return gps_time - self.gpstime

    def neighbors(self, neighborhood=None):
        if not self.gpstime:
            return []
        if self.group.name == 'Test':
            nearby = Event.objects.filter(group__name='Test')
        else:
            nearby = Event.objects.exclude(group__name='Test')
        delta1, delta2 = neighborhood or self.DEFAULT_EVENT_NEIGHBORHOOD
        nearby = nearby.filter(gpstime__range=(self.gpstime+delta1, self.gpstime+delta2))
        nearby = nearby.exclude(id=self.id)
        nearby = nearby.distinct()
        nearby = nearby.order_by('gpstime')
        return nearby

    @classmethod
    def getTypeLabel(cls, code):
        for key, label in cls.ANALYSIS_TYPE_CHOICES:
            if (key == code) or (code == label):
                return label
        raise KeyError("Unknown analysis type code: %s" % code)

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    @classmethod
    def getByGraceid(cls, id):
        try:
            e = cls.objects.filter(id=int(id[1:])).select_subclasses()[0]
        except IndexError:
            raise cls.DoesNotExist("Event matching query does not exist")
        if (id[0] == "T") and (e.group.name == "Test"):
            return e
        if (id[0] == "H") and (e.analysisType == "HWINJ"):
        if (id[0] == "E") and (e.analysisType == "GRB"):
            return e
        if (id[0] == "G"):
            return e
        raise cls.DoesNotExist("Event matching query does not exist")
    def __unicode__(self):
        return self.graceid()

    # Return a list of distinct tags associated with the log messages of this
    # event.
    def getAvailableTags(self):
        tagset_list = [log.tag_set.all() for log in self.eventlog_set.all()]
        taglist = []
        for tagset in tagset_list:
            for tag in tagset:
                taglist.append(tag)
        # Eliminate duplicates
        taglist = list(set(taglist))
        # Ordering should match the ordering of blessed tags list.
        # XXX Possibly, there are smarter ways of doing this.
        if settings.BLESSED_TAGS:
            availableTags = []
            for blessed_tag in settings.BLESSED_TAGS:
                for tag in taglist:
                    if tag.name == blessed_tag:
                        taglist.remove(tag)
                        availableTags.append(tag)
            # Append any remaining tags at the end of the list
            if len(taglist)>0:
                for tag in taglist:
                    availableTags.append(tag)
        else:
            availableTags = taglist
        return availableTags

    def getLogsForTag(self,tagname):
        loglist = []
        for log in self.eventlog_set.all():
            for tag in log.tag_set.all():
                if tag.name==tagname:
                    loglist.append(log)
        return loglist

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class EventLog(models.Model):
    class Meta:
        unique_together = ("event","N")
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    event = models.ForeignKey(Event, null=False)
    created = models.DateTimeField(auto_now_add=True)
    issuer = models.ForeignKey(DjangoUser)
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    filename = models.CharField(max_length=100, default="")
    comment = models.TextField(null=False)
    #XXX Does this need to be indexed for better performance?
    N = models.IntegerField(null=False)
    file_version = models.IntegerField(null=True)
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    def fileurl(self):
        if self.filename:
            if self.file_version >= 0:
                actual_filename += ',%d' % self.file_version
            return reverse('file', args=[self.event.graceid(), actual_filename])
            #return os.path.join(self.event.weburl(), 'private', self.filename)
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        else:
            return None

    def hasImage(self):
        # XXX hacky
        return self.filename and self.filename[-3:].lower() in ['png','gif','jpg']

    def save(self, *args, **kwargs):
        # XXX filename must not be 'None' because null=False for the filename
        # field above.
        self.filename = self.filename or ""
        attempts = 0
        while (not success and attempts < 5):
            attempts = attempts + 1
            if self.event.eventlog_set.count():
                self.N = int(self.event.eventlog_set.aggregate(models.Max('N'))['N__max']) + 1
            else:
                self.N = 1
            try:
                super(EventLog, self).save(*args, **kwargs)
                success = True
            except IntegrityError as e:
                # IntegrityError means an attempt to insert a duplicate
                # key or to violate a foreignkey constraint.
                # We are under race conditions.  Let's try again.
                pass

        if not success:
            # XXX Should this be a custom exception?  That way we could catch it
            # in the views that use it and give an informative error message.
            raise Exception("Too many attempts to save log message. Something is wrong.")
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class EMFacility(models.Model):
    name = models.CharField(max_length=200, unique=True)
    shortName = models.CharField(max_length=20, unique=True)

    # XXX what else? Possibly the liason. These can be populated 
    # automatically from the gw-astronomy COManage-provisioned LDAP.
    liason = models.ForeignKey(DjangoUser)

    # XXX Characteristics needed to produce pointings?

    def __unicode__(self):
        return self.name

EMSPECTRUM = (
('em.gamma',            'Gamma rays part of the spectrum'),
('em.gamma.soft',       'Soft gamma ray (120 - 500 keV)'),
('em.gamma.hard',       'Hard gamma ray (>500 keV)'),
('em.X-ray',            'X-ray part of the spectrum'),
('em.X-ray.soft',       'Soft X-ray (0.12 - 2 keV)'),
('em.X-ray.medium',     'Medium X-ray (2 - 12 keV)'),
('em.X-ray.hard',       'Hard X-ray (12 - 120 keV)'),
('em.UV',               'Ultraviolet part of the spectrum'),
('em.UV.10-50nm',       'Ultraviolet between 10 and 50 nm'),
('em.UV.50-100nm',      'Ultraviolet between 50 and 100 nm'),
('em.UV.100-200nm',     'Ultraviolet between 100 and 200 nm'),
('em.UV.200-300nm',     'Ultraviolet between 200 and 300 nm'),
('em.UV.FUV',           'Far-Infrared, 30-100 microns'),
('em.opt',              'Optical part of the spectrum'),
('em.opt.U',            'Optical band between 300 and 400 nm'),
('em.opt.B',            'Optical band between 400 and 500 nm'),
('em.opt.V',            'Optical band between 500 and 600 nm'),
('em.opt.R',            'Optical band between 600 and 750 nm'),
('em.opt.I',            'Optical band between 750 and 1000 nm'),
('em.IR',               'Infrared part of the spectrum'),
('em.IR.NIR',           'Near-Infrared, 1-5 microns'),
('em.IR.J',             'Infrared between 1.0 and 1.5 micron'),
('em.IR.H',             'Infrared between 1.5 and 2 micron'),
('em.IR.K',             'Infrared between 2 and 3 micron'),
('em.IR.MIR',           'Medium-Infrared, 5-30 microns'),
('em.IR.3-4um',         'Infrared between 3 and 4 micron'),
('em.IR.4-8um',         'Infrared between 4 and 8 micron'),
('em.IR.8-15um',        'Infrared between 8 and 15 micron'),
('em.IR.15-30um',       'Infrared between 15 and 30 micron'),
('em.IR.30-60um',       'Infrared between 30 and 60 micron'),
('em.IR.60-100um',      'Infrared between 60 and 100 micron'),
('em.IR.FIR',           'Far-Infrared, 30-100 microns'),
('em.mm',               'Millimetric part of the spectrum'),
('em.mm.1500-3000GHz',  'Millimetric between 1500 and 3000 GHz'),
('em.mm.750-1500GHz',   'Millimetric between 750 and 1500 GHz'),
('em.mm.400-750GHz',    'Millimetric between 400 and 750 GHz'),
('em.mm.200-400GHz',    'Millimetric between 200 and 400 GHz'),
('em.mm.100-200GHz',    'Millimetric between 100 and 200 GHz'),
('em.mm.50-100GHz',     'Millimetric between 50 and 100 GHz'),
('em.mm.30-50GHz',      'Millimetric between 30 and 50 GHz'),
('em.radio',            'Radio part of the spectrum'),
('em.radio.12-30GHz',   'Radio between 12 and 30 GHz'),
('em.radio.6-12GHz',    'Radio between 6 and 12 GHz'),
('em.radio.3-6GHz',     'Radio between 3 and 6 GHz'),
('em.radio.1500-3000MHz','Radio between 1500 and 3000 MHz'),
('em.radio.750-1500MHz','Radio between 750 and 1500 MHz'),
('em.radio.400-750MHz', 'Radio between 400 and 750 MHz'),
('em.radio.200-400MHz', 'Radio between 200 and 400 MHz'),
('em.radio.100-200MHz', 'Radio between 100 and 200 MHz'),
('em.radio.20-100MHz',  'Radio between 20 and 100 MHz'),
)

class EMBBEventLog(models.Model):
    """EMBB EventLog:  A multi-purpose annotation for EM followup.
     
    A rectangle on the sky, equatorially aligned,
    that has or will be imaged that is related to an event"""

    class Meta:
        ordering = ['-created', '-N']
        unique_together = ("event","N")

    # A counter for Eels associated with a given event. This is 
    # important for addressibility.
    N = models.IntegerField(null=False)
    
    # The time at which this Eel was created. Important for event auditing.
    created = models.DateTimeField(auto_now_add=True)

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    # The gracedb event that this Eel relates to
    event = models.ForeignKey(Event)

    # The responsible author of this communication
    submitter  = models.ForeignKey(DjangoUser)  # from a table of people

    # The instrument used or intended for the imaging implied by this footprint
    facility   = models.ForeignKey(EMFacility)       # from a table of facilities

    # Facility-local identifier for this footprint
    footprintID= models.CharField(max_length=200, blank=True)
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    # Now the global ID is a concatenation: facilityName#footprintID

    # the EM waveband used for the imaging as below
    waveband   = models.CharField(max_length=25, choices=EMSPECTRUM)

    # The center of the rectangular foorprint, right ascension and declination
    # in J2000 in decimal degrees
    ra         = models.FloatField(null=True)
    dec        = models.FloatField(null=True)

    # The width and height (RA range and Dec range) in decimal degrees
    raWidth    = models.FloatField(null=True)
    decWidth   = models.FloatField(null=True)

    # The GPS time of the middle of of the imaging time
    gpstime    = models.PositiveIntegerField(null=True)

    # The duration of the imaging in seconds
    duration   = models.PositiveIntegerField(null=True)

    # Event Log status
    EEL_STATUS_CHOICES = (('FO','FOOTPRINT'), ('SO','SOURCE'), ('CO','COMMENT'), ('CI','CIRCULAR'))
    eel_status     = models.CharField(max_length=2, choices=EEL_STATUS_CHOICES)

    # Observation status. If OBSERVATION, then there is a good chance of good image
    OBS_STATUS_CHOICES = (('NA', 'NOT APPLICABLE'), ('OB','OBSERVATION'), ('TE','TEST'), ('PR','PREDICTION'))
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    obs_status     = models.CharField(max_length=2, choices=OBS_STATUS_CHOICES)

    # This field is natural language for human
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    # This field is formal struct by a syntax TBD
    # for example  {"phot.mag.limit": 22.3}
    extra_info_dict = models.TextField(blank=True)
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    # We overload the 'save' method to avoid race conditions, since the Eels are numbered. 
    def save(self, *args, **kwargs):
        success = False
        attempts = 0
        while (not success and attempts < 5):
            attempts = attempts + 1
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            if self.event.embbeventlog_set.count():
                self.N = int(self.event.embbeventlog_set.aggregate(models.Max('N'))['N__max']) + 1
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                super(EMBBEventLog, self).save(*args, **kwargs)
                success = True
            except IntegrityError:
                # IntegrityError means an attempt to insert a duplicate
                # key or to violate a foreignkey constraint.
                # We are under race conditions.  Let's try again.
                pass

        if not success:
            # XXX Should this be a custom exception?  That way we could catch it
            # in the views that use it and give an informative error message.
            raise Exception("Too many attempts to save EMBB entry. Something is wrong.")
class Labelling(models.Model):
    event = models.ForeignKey(Event)
    label = models.ForeignKey(Label)
    creator = models.ForeignKey(DjangoUser)
    created = models.DateTimeField(auto_now_add=True)

# XXX Deprecated?  Is this used *anywhere*?
# Appears to only be used in models.py.  Here and Event class as approval_set
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class Approval(models.Model):
    COLLABORATION_CHOICES = ( ('L','LIGO'), ('V','Virgo'), )
    approver = models.ForeignKey(DjangoUser)
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    created = models.DateTimeField(auto_now_add=True)
    approvedEvent = models.ForeignKey(Event, null=False)
    approvingCollaboration = models.CharField(max_length=1, choices=COLLABORATION_CHOICES)

## Analysis Specific Attributes.

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class GrbEvent(Event):
    ivorn = models.CharField(max_length=200, null=True)
    author_ivorn = models.CharField(max_length=200, null=True)
    author_shortname = models.CharField(max_length=200, null=True)
    observatory_location_id = models.CharField(max_length=200, null=True)
    coord_system = models.CharField(max_length=200, null=True)
    ra = models.FloatField(null=True)
    dec = models.FloatField(null=True)
    error_radius = models.FloatField(null=True)
    how_description = models.CharField(max_length=200, null=True)
    how_reference_url = models.URLField(null=True)

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class CoincInspiralEvent(Event):
    ifos             = models.CharField(max_length=20, default="")
    end_time         = models.PositiveIntegerField(null=True)
    end_time_ns      = models.PositiveIntegerField(null=True)
    mass             = models.FloatField(null=True)
    mchirp           = models.FloatField(null=True)
    minimum_duration = models.FloatField(null=True)
    snr              = models.FloatField(null=True)
    false_alarm_rate = models.FloatField(null=True)
    combined_far     = models.FloatField(null=True)


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class MultiBurstEvent(Event):
    ifos             = models.CharField(max_length=20, default="")
    start_time       = models.PositiveIntegerField(null=True)
    start_time_ns    = models.PositiveIntegerField(null=True)
    duration         = models.FloatField(null=True)
    peak_time        = models.PositiveIntegerField(null=True)
    peak_time_ns     = models.PositiveIntegerField(null=True)
    central_freq     = models.FloatField(null=True)
    bandwidth        = models.FloatField(null=True)
    amplitude        = models.FloatField(null=True)
    snr              = models.FloatField(null=True)
    confidence       = models.FloatField(null=True)
    false_alarm_rate = models.FloatField(null=True)
    ligo_axis_ra     = models.FloatField(null=True)
    ligo_axis_dec    = models.FloatField(null=True)
    ligo_angle       = models.FloatField(null=True)
    ligo_angle_sig   = models.FloatField(null=True)

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class SingleInspiral(models.Model):
    event             = models.ForeignKey(Event, null=False)
    ifo               = models.CharField(max_length=20, null=True)
    search            = models.CharField(max_length=20, null=True)
    channel           = models.CharField(max_length=20)
    end_time          = models.IntegerField(null=True)
    end_time_ns       = models.IntegerField(null=True)
    end_time_gmst     = models.FloatField(null=True)
    impulse_time      = models.IntegerField(null=True)
    impulse_time_ns   = models.IntegerField(null=True)
    template_duration = models.FloatField(null=True)
    event_duration    = models.FloatField(null=True)
    amplitude         = models.FloatField(null=True)
    eff_distance      = models.FloatField(null=True)
    coa_phase         = models.FloatField(null=True)
    mass1             = models.FloatField(null=True)
    mass2             = models.FloatField(null=True)
    mchirp            = models.FloatField(null=True)
    mtotal            = models.FloatField(null=True)
    eta               = models.FloatField(null=True)
    kappa             = models.FloatField(null=True)
    chi               = models.FloatField(null=True)
    tau0              = models.FloatField(null=True)
    tau2              = models.FloatField(null=True)
    tau3              = models.FloatField(null=True)
    tau4              = models.FloatField(null=True)
    tau5              = models.FloatField(null=True)
    ttotal            = models.FloatField(null=True)
    psi0              = models.FloatField(null=True)
    psi3              = models.FloatField(null=True)
    alpha             = models.FloatField(null=True)
    alpha1            = models.FloatField(null=True)
    alpha2            = models.FloatField(null=True)
    alpha3            = models.FloatField(null=True)
    alpha4            = models.FloatField(null=True)
    alpha5            = models.FloatField(null=True)
    alpha6            = models.FloatField(null=True)
    beta              = models.FloatField(null=True)
    f_final           = models.FloatField(null=True)
    snr               = models.FloatField(null=True)
    chisq             = models.FloatField(null=True)
    chisq_dof         = models.IntegerField(null=True)
    bank_chisq        = models.FloatField(null=True)
    bank_chisq_dof    = models.IntegerField(null=True)
    cont_chisq        = models.FloatField(null=True)
    cont_chisq_dof    = models.IntegerField(null=True)
    sigmasq           = models.FloatField(null=True)
    rsqveto_duration  = models.FloatField(null=True)
    Gamma0            = models.FloatField(null=True)
    Gamma1            = models.FloatField(null=True)
    Gamma2            = models.FloatField(null=True)
    Gamma3            = models.FloatField(null=True)
    Gamma4            = models.FloatField(null=True)
    Gamma5            = models.FloatField(null=True)
    Gamma6            = models.FloatField(null=True)
    Gamma7            = models.FloatField(null=True)
    Gamma8            = models.FloatField(null=True)
    Gamma9            = models.FloatField(null=True)

    def end_time_full(self):
        return LIGOTimeGPS(self.end_time, self.end_time_ns)

    def impulse_time_full(self):
        return LIGOTimeGPS(self.impulse_time, self.impulse_time_ns)

    @classmethod
    def create_events_from_ligolw_table(cls, table, event):
        """For an Event, given a table (loaded by ligolw.utils.load_filename or similar) create SingleEvent tables for the event"""

        field_names = cls.field_names()
        created_events = []

        log.debug("Single/create from table/fields: " + str(field_names))

        for row in table:
            e = cls(event=event)
            log.debug("Single/creating event")
            for column in field_names:
                value = getattr(row, column)
                log.debug("Setting column '%s' with value '%s'" % (column, value))
                setattr(e, column, value)
            e.save()
            created_events.append(e)

        return created_events

    @classmethod
    def update_event(cls, event, datafile=None):
        """Given an Event (and optional location of coinc.xml) update SingleInspiral data"""
        # XXX Need a better way to find original data.
        if datafile is None:
            datafile = os.path.join(event.datadir(), 'coinc.xml')

        try:
            xmldoc = glue.ligolw.utils.load_filename(datafile)
        except IOError:
            return None

        # Extract Single Inspiral Information
        s_inspiral_tables = glue.ligolw.table.getTablesByName(
                xmldoc,
                glue.ligolw.lsctables.SnglInspiralTable.tableName)

        # Concatentate the tables' rows into a single table
        table = sum(s_inspiral_tables, [])

        event.singleinspiral_set.all().delete()

        return cls.create_events_from_ligolw_table(table, event)

    @classmethod
    def field_names(cls):
        try:
            return cls._field_names
        except AttributeError: pass
        model_field_names = set([ x.name for x in cls._meta.fields ])
        ligolw_field_names = set(
                glue.ligolw.lsctables.SnglInspiralTable.validcolumns.keys())

        cls._field_names = model_field_names.intersection(ligolw_field_names)
        return cls._field_names


## Tags (user-defined log message attributes)
class Tag(models.Model):
    # XXX Does the tag need to have a submitter column?
    # No, because creating a tag will generate a log message.
    # For the same reason, a timstamp is not necessary.
    eventlogs   = models.ManyToManyField(EventLog)
    name        = models.CharField(max_length=100)
    displayName = models.CharField(max_length=200,null=True)
    def __unicode__(self):
        if self.displayName:
            return self.displayName
        else:
            return self.name

#     def getEvents(self):
#         # XXX Any way of doing this with filters?
#         # We would need to filter for a non-null intersection of the 
#         # set of log messages in the event with the set of log 
#         # messages in the tag.
#         eventlist = [log.event for log in self.eventlogs.all()]