Esempio n. 1
0
 def get_TEC_pp(self,radec,pol=0,new_stat_select=None):
    TEC_out=[]      
    N_stations = len(self.stat_select[:])
    N_sources = len(self.sources)
    N_piercepoints = N_stations * N_sources
    h=self.piercepoints.attrs.height
    r_0 = self.TECfit_white.attrs.r_0
    beta = self.TECfit_white.attrs.beta
    pp_out=[]
    am_out=[]
    TEC_out=[]
    stations=self.station_positions[:]
    if not (new_stat_select is None):
       stations=stations[new_stat_select]
    for i in range(len(self.n_list)) :
       if i%10==0:
          sys.stdout.write(str(i)+'...')
          sys.stdout.flush()                
       time=self.times[i]
       piercepoints=PosTools.getPiercePoints(time,radec.reshape((1,-1)),stations,height=h)
       pp=piercepoints.positions_xyz
       am=piercepoints.zenith_angles
       pp_out.append(pp)
       am_out.append(am)
       Xp_table=reshape(self.piercepoints[i]['positions_xyz'], (N_piercepoints, 3))
       #v=self.TECfit_white[ i, :, : ,pol][self.stat_select[:]].reshape((N_piercepoints,1))
       v=self.TECfit_white[ i, :, : ,pol][self.stat_select[:]].reshape((N_piercepoints,1))
       tecs=[]
       for ist in range(stations[:].shape[0]):
          tecs.append(get_interpolated_TEC_white(Xp_table,v,beta,r_0,pp[0,ist]))
       TEC_out.append(tecs)
    return array(pp_out),array(am_out),array(TEC_out)
Esempio n. 2
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   def calculate_Sage_piercepoints(self, sage_group=0,time_steps = [], station_select=[],height = 200.e3):
      if ( len( time_steps ) == 0 ):
         n_list = range( self.times[:].shape[0] )
      else:
         n_list = time_steps
      self.sage_n_list = n_list
      if 'sage%d_n_list'%sage_group in self.hdf5.root: self.hdf5.removeNode('\sage%d_n_list'%sage_group)
      self.hdf5.createArray(self.hdf5.root, 'sage%d_n_list'%sage_group, self.sage_n_list)
      if ( len( station_select ) == 0 ):
         stat_select = range( self.stations[:].shape[0] )
      else:
         stat_select = station_select
      self.sage_stat_select = stat_select
      if 'sage%d_stat_select'%sage_group in self.hdf5.root: self.hdf5.removeNode('\sage%d_stat_select'%sage_group)
      self.hdf5.createArray(self.hdf5.root,'sage%d_stat_select'%sage_group, self.sage_stat_select)


      self.sage_height = height

      N_stations=len(stat_select)
      if 'sage%d_piercepoints'%sage_group in self.hdf5.root: self.hdf5.removeNode('\sage%d_piercepoints'%sage_group)
      description = {'positions':tables.Float64Col((self.N_sources, N_stations,2)), \
                     'positions_xyz':tables.Float64Col((self.N_sources, N_stations,3)), \
                     'zenith_angles':tables.Float64Col((self.N_sources, N_stations))}
      self.sage_piercepoints = self.hdf5.createTable(self.hdf5.root,'sage%d_piercepoints'%sage_group, description)
      self.sage_piercepoints.attrs.height = self.sage_height
      piercepoints_row = self.sage_piercepoints.row
      source_positions=self.hdf5.getNode('sage_radec%d'%sage_group)[:]
      p = ProgressBar(len(n_list), "Calculating piercepoints: ")
      for (n, counter) in zip(n_list, range(len(n_list))):
         p.update(counter)
         
         piercepoints=PosTools.getPiercePoints(self.times[n],source_positions,self.station_positions[:][self.stat_select[:]],height=self.sage_height)
         #piercepoints =  PiercePoints( self.times[ n ], self.pointing, self.array_center, self.source_positions, self.station_positions[:][self.stat_select[:]], height = self.height )
         piercepoints_row['positions'] = piercepoints.positions
         piercepoints_row['positions_xyz'] = piercepoints.positions_xyz
         piercepoints_row['zenith_angles'] = piercepoints.zenith_angles
         piercepoints_row.append()
      self.sage_piercepoints.flush()
      p.finished()
Esempio n. 3
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def getTEC(MS=None,
           server="ftp://ftp.unibe.ch/aiub/CODE/",
           prefix='CODG',
           ionexPath="IONEXdata/",
           earth_rot=0,ha_limit=-1000,
           **kwargs):
    '''optional arguments are  radec or pointing : [ra,dec] in radians,
    azel : [az,el] in radians, If azel is specified, radec will be ignored
    timestep in s, timerange = [start, end]in MJD seconds, 
    otherwise use start_time/end_time (either MJD or casa timestring (NEEDS PYRAP), eg. 2012/11/21/12:00:00  or 56252.5d  ),    
    stat_names = list of strings per station, 
    stat_positions = list of length 3 numpy arrays, containing station_position in ITRF meters.
    Returns the (timegrid,timestep,TEC) where TEC is a dictionary containing 1 enumpyarray per station in stat_names. 
    If stat_names is not given, the station names will either be extracted from the MS or st1...stN '''

    stat_names=[]
    stat_pos=[PosTools.posCS002]
    #stat_names=['LOFAR_CS002']
    # the following parameter is used to extend the observation range by 120 sec
    # before and after the actual specified time. If we want to correct an
    # actual data set, this is required for the scipy 1d interpolation routine to
    # ensure that the calculated range of data exceeds the time range actually
    # observed - I have used the same value in ALBUS - Tony
    TIME_OFFSET = 0
    if not (MS is None):

        (timerange,timestep,pointing,stat_names,stat_pos)=PosTools.getMSinfo(MS);
    useAzel=False
    for key in kwargs.keys():
        if not useAzel and (key=='radec' or key=='pointing'):
            pointing = kwargs[key]
        if key=='start_time':
            start_time=kwargs[key]
            time_in_sec = False
        if key=='end_time':
            end_time=kwargs[key]
            time_in_sec = False
        if key=='azel':
            pointing = kwargs[key]
            useAzel=True
        if key=='timestep':
            timestep=kwargs[key]
        if key=='timerange':
            timerange=kwargs[key]
        if key=='stat_names':
            stat_names=kwargs[key]
        if key=='TIME_OFFSET':
           TIME_OFFSET=kwargs[key]
        if key=='stat_positions':
            stat_pos=kwargs[key]
            if not stat_names:
                stat_names =['st%d'%(i+1) for i in range(len(stat_pos))]

    if timerange != 0:
      start_time = timerange[0]-TIME_OFFSET
      end_time = timerange[1]+TIME_OFFSET
      time_in_sec = True
      reference_time = start_time
      str_start_time=PosTools.obtain_observation_year_month_day_hms(reference_time)
    else:
        timerange,str_start_time,reference_time=PosTools.get_time_range(start_time,end_time,timestep,time_in_sec,TIME_OFFSET)
    if str_start_time==-1:
       return

    #IONEX files go per day, check if more than one file is  needed.
    times,timerange=PosTools.getIONEXtimerange(timerange,timestep)
    times.append(np.arange(timerange[0],timerange[1]+timestep,timestep)) #add one extra step to make sure you have a value for all times in the MS in case timestep hase been changed
    timegrid=np.array([])
    TECs={};
    ams={};
    flags={}
    for st in stat_names:
        TECs[st]=[]
        ams[st]=[]
        flags[st]=[]
    for time_array in times:
        #get RM per timeslot
        starttime=time_array[0];
        date_parms =  PosTools.obtain_observation_year_month_day_fraction(starttime)
        #get relevant ionex file
        ionexf=ionex.getIONEXfile(time=date_parms,server=server,prefix=prefix,outpath=ionexPath)
        if ionexf==-1:
            print "error opening ionex data"
            return
       
        tecinfo=ionex.readTEC(ionexf)
        for station,position in  zip(stat_names,stat_pos):
          #print "getting TEC for",station,"at",position,"time",time_array 
          for time in time_array:
            result =  PosTools.obtain_observation_year_month_day_fraction(time)
            part_of_day= result[3] * 24
            if useAzel:
                  az=pointing[0]
                  #el=0.5*np.pi-pointing[1]
                  el=pointing[1]
                  flags[station].append(1)
            else:

                az,el=PosTools.getAzEl(pointing,time,position,ha_limit)
                if az==-1 and el==-1:
                    return
                if az==999 and el==999:
                    #outsite hadec range
                    TECs[station].append(-999)  #sTEC value
                    ams[station].append(-999)
                    flags[station].append(0)
                    continue
                flags[station].append(1) 
            latpp,lonpp,height,lon,lat,am1=PosTools.getlonlatheight(az,el,position)
            if latpp==-1 and lonpp==-1 and height==-1:
               return
            vTEC=ionex.getTECinterpol(time=part_of_day,lat=latpp,lon=lonpp,tecinfo=tecinfo,apply_earth_rotation=earth_rot)

            TECs[station].append(vTEC)  #sTEC value
            ams[station].append(am1)
        timegrid=np.concatenate((timegrid,time_array));
    
    for st in stat_names:
            TECs[st]=np.array(TECs[st])
            ams[st]=np.array(ams[st])
            flags[st]=np.array(flags[st])
    return (timegrid,timestep,TECs,ams,flags)
Esempio n. 4
0
def getRM(MS=None,
          server="ftp://ftp.unibe.ch/aiub/CODE/",
          prefix='CODG',
          ionexPath="IONEXdata/",
          earth_rot=0,
          timerange=0,
          use_azel=False,
          ha_limit=-1000,
          use_filter=None,
          **kwargs):
    '''optional arguments are:
    radec or pointing : [ra,dec] in radians, or if use_azel =True, az + el in radians,
    timestep in s, timerange = [start, end]in MJD seconds, 
    otherwise use start_time/end_time (casa timestring,eg. 2012/11/21/12:00:00  or 56252.5d  NEEDS PYRAP) ,
    stat_names = list of strings per station, 
    stat_positions = list of length 3 numpy arrays, containing station_position in ITRF meters.
    useEMM = boolean, use EMM for Earth magnetic field, otherwise WMM cooefficients will be used.
    out_file = string, if given the data points will be written to a text file.
    use_mean = True if you only want report for mean of station positions
    use_filter =standard deviation,or list of standard deviations (time,long, lat) to gaussian filter TEC data 
    TIME_OFFSET = float, offset time at start and end to ensure all needed values are calculated,
    Returns the (timegrid,timestep,TEC) where TEC is a dictionary containing 1 enumpyarray per station in stat_names. 
    If stat_names is not given, the station names will either be extracted from the MS or st1...stN '''

    print('earth_rot', earth_rot)
    print('timerange ', timerange)
    print('use_azel ', use_azel)
    stat_names = []
    useEMM = False
    use_mean = False
    myobject = ''
    timestep = 60
    pointing = [0., 0.5 * np.pi]
    out_file = ''
    stat_pos = [PosTools.posCS002]
    #stat_names=['LOFAR_CS002']
    if not (MS is None):

        (timerange, timestep, pointing, stat_names,
         stat_pos) = PosTools.getMSinfo(MS)

    for key in kwargs.keys():
        if key == 'use_mean':
            use_mean = kwargs[key]
            stat_pos_mean = False
        if key == 'radec' or key == 'pointing':
            pointing = kwargs[key]
        if key == 'object':
            myobject = kwargs[key]
            #out_file = 'RMextract_report_' + myobject
        if key == 'start_time':
            start_time = kwargs[key]
            time_in_sec = False
        if key == 'end_time':
            end_time = kwargs[key]
            time_in_sec = False
        if key == 'timestep':
            timestep = kwargs[key]
        if key == 'stat_names':
            stat_names = kwargs[key]
        if key == 'out_file':
            out_file = kwargs[key]
        if key == 'TIME_OFFSET':
            TIME_OFFSET = kwargs[key]
        if key == 'stat_positions':
            stat_pos = kwargs[key]
            if not stat_names:
                stat_names = ['st%d' % (i + 1) for i in range(len(stat_pos))]
        if key == 'useEMM':
            useEMM = kwargs[key]
#
    if timerange != 0:
        start_time = timerange[0]
        end_time = timerange[1]
        time_in_sec = True
        reference_time = start_time
        timerange[0] = start_time - timestep
        timerange[1] = end_time + timestep
        str_start_time = PosTools.obtain_observation_year_month_day_hms(
            reference_time)
    else:
        timerange, str_start_time, reference_time = PosTools.get_time_range(
            start_time, end_time, timestep, time_in_sec, 0)
    if str_start_time == -1:
        return

    if useEMM:
        print("USING EMM for EarthMagnetic Field")
        emm = EMM.EMM()
    else:
        emm = EMM.WMM()

    times, timerange = PosTools.getIONEXtimerange(timerange, timestep)
    if len(times[-1]) == 0 or times[-1][-1] < timerange[1]:
        timestmp = list(times[-1])
        timestmp.append(
            timerange[1]
        )  #add one extra step to make sure you have a value for all times in the MS in case timestep hase been changed
        times[-1] = np.array(timestmp)
    timegrid = np.array([])
    TECs = {}
    Bs = {}
    Bpars = {}
    air_mass = {}
    RMs = {}
    azimuth = {}
    elevation = {}
    flags = {}
    if len(out_file) and len(myobject):
        out_file = out_file + '_' + myobject
    else:
        if len(myobject):
            out_file = 'RMextract_report_' + myobject
# print header section of report
    if len(out_file):
        if os.path.exists(out_file):
            os.remove(out_file)
        log = open(out_file, 'a')
        log.write('Observing %s\n' % myobject)
        if not (MS is None):
            log.write('Using measurement set %s\n' % MS)
        if use_azel:
            log.write('observing at a fixed azimuth and elevation \n')
        log.write('station_positions %s \n' % stat_pos)
        log.write('\n')

    for st in stat_names:
        azimuth[st] = []
        elevation[st] = []
        air_mass[st] = []
        Bs[st] = []
        Bpars[st] = []
        RMs[st] = []
        TECs[st] = []
        air_mass[st] = []
        flags[st] = []
    for time_array in times:
        #get RM per timeslot
        starttime = time_array[0]
        print "getting ionexfile for", starttime
        date_parms = PosTools.obtain_observation_year_month_day_fraction(
            starttime)
        dayofyear = date(date_parms[0], date_parms[1],
                         date_parms[2]).timetuple().tm_yday
        emm.date = date_parms[0] + float(dayofyear) / 365.
        #get relevant ionex file
        ionexf = ionex.getIONEXfile(time=date_parms,
                                    server=server,
                                    prefix=prefix,
                                    outpath=ionexPath)
        if ionexf == -1:
            print "error opening ionex data"
            return
        tecinfo = ionex.readTEC(ionexf, use_filter=use_filter)
        if use_mean:
            if not stat_pos_mean:
                stn_mean = stat_pos.mean(0)
                stat_pos = []
                stat_pos.append(stn_mean)
                stat_pos_mean = True
                print 'stat_pos.mean', stn_mean
        for station, position in zip(stat_names, stat_pos):
            print('generating data for station ', station)

            for time in time_array:
                result = PosTools.obtain_observation_year_month_day_fraction(
                    time)
                part_of_day = result[3] * 24
                if use_azel:
                    az = pointing[0]
                    el = pointing[1]
                    flags[station].append(1)
                else:
                    az, el = PosTools.getAzEl(pointing, time, position,
                                              ha_limit)
                    if az == -1 and el == -1:
                        return
                    if az == 999 and el == 999:
                        #outsite hadec range
                        air_mass[station].append(-999)
                        azimuth[station].append(-999)
                        elevation[station].append(-999)
                        Bs[station].append([-999, -999, -999])
                        Bpars[station].append(-999)
                        RMs[station].append(-999)
                        TECs[station].append(-999)  #sTEC value
                        flags[station].append(0)
                        continue
                flags[station].append(1)
                latpp, lonpp, height, lon, lat, am1 = PosTools.getlonlatheight(
                    az, el, position)
                if latpp == -1 and lonpp == -1 and height == -1:
                    return
                #get VTEC from IONEX interpolation
                vTEC = ionex.getTECinterpol(time=part_of_day,
                                            lat=latpp,
                                            lon=lonpp,
                                            tecinfo=tecinfo,
                                            apply_earth_rotation=earth_rot)

                TECs[station].append(vTEC * am1)  #STEC value
                emm.lon = lonpp
                emm.lat = latpp
                emm.h = ION_HEIGHT / 1.0e3
                Bpar = -1 * emm.getProjectedField(
                    lon,
                    lat)  # minus sign since the radiation is towards the Earth
                BField = emm.getXYZ()
                Bs[station].append(BField)

                air_mass[station].append(am1)
                azimuth[station].append(az)
                elevation[station].append(el)
                Bpars[station].append(Bpar)
                #calculate RM constant comes from VtEC in TECU,B in nT, RM = 2.62
                RMs[station].append((Bpar * vTEC * am1) * 2.62e-6)
            if use_mean:
                break

        timegrid = np.concatenate((timegrid, time_array))

    for st in stat_names:
        air_mass[station] = np.array(air_mass[st])
        azimuth[station] = np.array(azimuth[st])
        elevation[station] = np.array(elevation[st])
        TECs[st] = np.array(TECs[st])
        Bs[st] = np.array(Bs[st])
        Bpars[st] = np.array(Bpars[st])
        RMs[st] = np.array(RMs[st])
        flags[st] = np.array(flags[st])
        if use_mean:
            break

    big_dict = {}
    big_dict['STEC'] = TECs
    big_dict['Bpar'] = Bpars
    big_dict['BField'] = Bs
    big_dict['AirMass'] = air_mass
    big_dict['elev'] = elevation
    big_dict['azimuth'] = azimuth
    big_dict['RM'] = RMs
    big_dict['times'] = timegrid
    big_dict['timestep'] = timestep
    big_dict['station_names'] = stat_names
    big_dict['stat_pos'] = stat_pos
    big_dict['flags'] = flags
    big_dict['reference_time'] = reference_time
    # finish writing computed data to report
    if len(out_file):
        time_range = [big_dict['times'][0], big_dict['times'][-1]]
        log.write('start and end times %s %s \n' %
                  (time_range[0], time_range[1]))
        log.write(
            'reference time for rel_time=0: year month day hr min sec %s %s %s %s %s %s \n'
            % str_start_time)
        if use_azel:
            log.write('observing at azimuth and elevation %s %s \n' %
                      (pointing[0], pointing[1]))
        else:
            log.write('observation direction %s %s \n' %
                      (pointing[0], pointing[1]))
        log.write('\n')
        k = 0
        for key in big_dict['station_names']:
            seq_no = 0
            if use_mean:
                log.write('data for station mean position at %s\n' %
                          (stat_pos[k]))
            else:
                log.write('data for station %s  at position %s\n' %
                          (key, stat_pos[k]))
            log.write(
                'seq  rel_time time_width El         Az         STEC           RM (rad/m2)   VTEC factor  \n'
            )
            for i in range(timegrid.shape[0]):
                el = big_dict['elev'][key][i]
                if el < 0:
                    ok = 1
                    stec = 0.0
                    rm = 0.0
                    vtec_factor = 1.0
                else:
                    ok = 0
                    stec = big_dict['STEC'][key][i]
                    rm = big_dict['RM'][key][i]
                    vtec_factor = 1.0 / big_dict['AirMass'][key][i]
                az = big_dict['azimuth'][key][i]
                rel_time = timegrid[i] - reference_time
                if i == 0:
                    time_width = reference_time - timegrid[i]
                else:
                    time_width = timegrid[i] - timegrid[i - 1]
                log.write("%s : %s %s %s %s %s %s %s %s\n" %
                          (seq_no, ok, rel_time, time_width, el, az, stec, rm,
                           vtec_factor))
                seq_no = seq_no + 1
            k = k + 1
            if use_mean:
                break
            log.write(' \n')
        log.close()
        print('****** finished ionosphere predictions report: ', out_file)
    else:
        print('*********** finished ionosphere predictions ***************')

    return big_dict
Esempio n. 5
0
def getRM(MS=None,
           server="ftp://ftp.unibe.ch/aiub/CODE/",
           prefix='CODG',
           ionexPath="IONEXdata/",
           earth_rot=0,
           timerange=0,
           use_azel = False,ha_limit=-1000,use_filter=None,
           **kwargs):
    '''optional arguments are:
    radec or pointing : [ra,dec] in radians, or if use_azel =True, az + el in radians,
    timestep in s, timerange = [start, end]in MJD seconds, 
    otherwise use start_time/end_time (casa timestring,eg. 2012/11/21/12:00:00  or 56252.5d  NEEDS PYRAP) ,
    stat_names = list of strings per station, 
    stat_positions = list of length 3 numpy arrays, containing station_position in ITRF meters.
    useEMM = boolean, use EMM for Earth magnetic field, otherwise WMM cooefficients will be used.
    out_file = string, if given the data points will be written to a text file.
    use_mean = True if you only want report for mean of station positions
    use_filter =standard deviation,or list of standard deviations (time,long, lat) to gaussian filter TEC data 
    TIME_OFFSET = float, offset time at start and end to ensure all needed values are calculated,
    Returns the (timegrid,timestep,TEC) where TEC is a dictionary containing 1 enumpyarray per station in stat_names. 
    If stat_names is not given, the station names will either be extracted from the MS or st1...stN '''

    print ('earth_rot', earth_rot)
    print ('timerange ', timerange)
    print ('use_azel ', use_azel)
    stat_names=[]
    useEMM=False
    use_mean = False
    myobject = ''
    timestep=60
    pointing=[0.,0.5*np.pi]
    out_file=''
    stat_pos=[PosTools.posCS002]
    #stat_names=['LOFAR_CS002']
    if not (MS is None):

      (timerange,timestep,pointing,stat_names,stat_pos)=PosTools.getMSinfo(MS);
    
    for key in kwargs.keys():
        if key=='use_mean':
            use_mean = kwargs[key]
            stat_pos_mean = False
        if key=='radec' or key=='pointing':
            pointing = kwargs[key]
        if key=='object':
            myobject = kwargs[key]
            #out_file = 'RMextract_report_' + myobject
        if key=='start_time':
            start_time=kwargs[key]
            time_in_sec = False
        if key=='end_time':
            end_time=kwargs[key]
            time_in_sec = False
        if key=='timestep':
            timestep=kwargs[key]
        if key=='stat_names':
            stat_names=kwargs[key]
        if key=='out_file':
            out_file=kwargs[key]
        if key=='TIME_OFFSET':
           TIME_OFFSET=kwargs[key]
        if key=='stat_positions':
            stat_pos=kwargs[key]
            if not stat_names:
                stat_names =['st%d'%(i+1) for i in range(len(stat_pos))]
        if key=='useEMM':
            useEMM=kwargs[key]
#      
    if timerange != 0:
      start_time = timerange[0]
      end_time = timerange[1]
      time_in_sec = True
      reference_time = start_time
      timerange[0] = start_time - timestep
      timerange[1] = end_time + timestep
      str_start_time=PosTools.obtain_observation_year_month_day_hms(reference_time)
    else:
        timerange,str_start_time,reference_time=PosTools.get_time_range(start_time,end_time,timestep,time_in_sec,0)
    if str_start_time==-1:
       return
        
    if useEMM:
        print ("USING EMM for EarthMagnetic Field")
        emm=EMM.EMM()
    else:
        emm=EMM.WMM()
    
    times,timerange=PosTools.getIONEXtimerange(timerange,timestep)
    if len(times[-1])==0 or times[-1][-1]<timerange[1]:
        timestmp=list(times[-1])
        timestmp.append(timerange[1]) #add one extra step to make sure you have a value for all times in the MS in case timestep hase been changed
        times[-1]=np.array(timestmp)
    timegrid=np.array([])
    TECs={};
    Bs={}
    Bpars={}
    air_mass={};
    RMs={};
    azimuth={};
    elevation={};
    flags={}
    if len(out_file) and len(myobject):
        out_file = out_file + '_' + myobject
    else:
      if len(myobject):
        out_file = 'RMextract_report_' + myobject
# print header section of report
    if len(out_file):
       if os.path.exists(out_file):
         os.remove(out_file)
       log = open(out_file, 'a')
       log.write ('Observing %s\n' % myobject)
       if not (MS is None):
           log.write ('Using measurement set %s\n' % MS)
       if use_azel:
         log.write ('observing at a fixed azimuth and elevation \n')
       log.write ('station_positions %s \n' % stat_pos)
       log.write ('\n')

    for st in stat_names:
        azimuth[st] = []
        elevation[st] = []
        air_mass[st] = []
        Bs[st]=[]
        Bpars[st]=[]
        RMs[st]=[]
        TECs[st]=[]
        air_mass[st]=[]
        flags[st]=[]
    for time_array in times:
        #get RM per timeslot
        starttime=time_array[0]
        print "getting ionexfile for",starttime
        date_parms =  PosTools.obtain_observation_year_month_day_fraction(starttime)
        dayofyear = date(date_parms[0],date_parms[1],date_parms[2]).timetuple().tm_yday  
        emm.date=date_parms[0]+float(dayofyear)/365.
        #get relevant ionex file
        ionexf=ionex.getIONEXfile(time=date_parms,server=server,prefix=prefix,outpath=ionexPath)
        if ionexf==-1:
           print "error opening ionex data"
           return
        tecinfo=ionex.readTEC(ionexf,use_filter=use_filter)
        if use_mean:
          if not stat_pos_mean:
            stn_mean = stat_pos.mean(0)
            stat_pos = []
            stat_pos.append(stn_mean)
            stat_pos_mean = True
            print 'stat_pos.mean', stn_mean
        for station,position in  zip(stat_names,stat_pos):
          print ('generating data for station ', station)
 
          
          for time in time_array:
            result =  PosTools.obtain_observation_year_month_day_fraction(time)
            part_of_day= result[3] * 24
            if use_azel:
              az = pointing[0]
              el = pointing[1]
              flags[station].append(1)   
            else:
               az,el = PosTools.getAzEl(pointing,time,position,ha_limit)
               if az==-1 and el==-1:
                  return
               if az==999 and el==999:
                    #outsite hadec range
                  air_mass[station].append(-999)
                  azimuth[station].append(-999)
                  elevation[station].append(-999)
                  Bs[station].append([-999,-999,-999])
                  Bpars[station].append(-999)
                  RMs[station].append(-999)
                  TECs[station].append(-999)  #sTEC value
                  flags[station].append(0)
                  continue
            flags[station].append(1)   
            latpp,lonpp,height,lon,lat,am1=PosTools.getlonlatheight(az,el,position)
            if latpp==-1 and lonpp==-1 and height==-1:
               return
            #get VTEC from IONEX interpolation
            vTEC=ionex.getTECinterpol(time=part_of_day,lat=latpp,lon=lonpp,tecinfo=tecinfo,apply_earth_rotation=earth_rot)

            TECs[station].append(vTEC*am1)  #STEC value
            emm.lon = lonpp
            emm.lat = latpp
            emm.h= ION_HEIGHT / 1.0e3
            Bpar=-1*emm.getProjectedField(lon,lat)# minus sign since the radiation is towards the Earth
            BField=emm.getXYZ()
            Bs[station].append(BField)

            air_mass[station].append(am1)
            azimuth[station].append(az)
            elevation[station].append(el)
            Bpars[station].append(Bpar)
            #calculate RM constant comes from VtEC in TECU,B in nT, RM = 2.62
            RMs[station].append((Bpar*vTEC*am1)*2.62e-6)
          if use_mean:
            break

            
        timegrid=np.concatenate((timegrid,time_array));
    
    for st in stat_names:
      air_mass[station] = np.array(air_mass[st])
      azimuth[station] = np.array(azimuth[st])
      elevation[station] = np.array(elevation[st])
      TECs[st]=np.array(TECs[st])
      Bs[st]=np.array(Bs[st])
      Bpars[st]=np.array(Bpars[st])
      RMs[st]=np.array(RMs[st]) 
      flags[st]=np.array(flags[st])
      if use_mean:
        break
       
    big_dict={}
    big_dict['STEC']=TECs
    big_dict['Bpar']=Bpars
    big_dict['BField']=Bs
    big_dict['AirMass']=air_mass
    big_dict['elev']=elevation
    big_dict['azimuth']=azimuth
    big_dict['RM']=RMs 
    big_dict['times']=timegrid
    big_dict['timestep']=timestep
    big_dict['station_names'] = stat_names
    big_dict['stat_pos'] = stat_pos
    big_dict['flags'] = flags
    big_dict['reference_time'] = reference_time 
    # finish writing computed data to report
    if len(out_file):
       time_range=[big_dict['times'][0],big_dict['times'][-1]]
       log.write ('start and end times %s %s \n' % (time_range[0], time_range[1]))
       log.write ('reference time for rel_time=0: year month day hr min sec %s %s %s %s %s %s \n' % str_start_time)
       if use_azel:
         log.write ('observing at azimuth and elevation %s %s \n' % (pointing[0], pointing[1]))
       else:
         log.write ('observation direction %s %s \n' % (pointing[0], pointing[1]))
       log.write ('\n')
       k = 0
       for key in big_dict['station_names']:
         seq_no = 0
         if use_mean:
           log.write ('data for station mean position at %s\n' % (stat_pos[k]))
         else:
           log.write ('data for station %s  at position %s\n' % (key, stat_pos[k]))
         log.write ('seq  rel_time time_width El         Az         STEC           RM (rad/m2)   VTEC factor  \n')
         for i in range (timegrid.shape[0]):
           el = big_dict['elev'][key][i]
           if el < 0 :
             ok = 1
             stec = 0.0
             rm = 0.0
             vtec_factor = 1.0
           else:
             ok = 0
             stec =big_dict['STEC'][key][i]
             rm = big_dict['RM'][key][i]
             vtec_factor = 1.0 / big_dict['AirMass'][key][i]
           az = big_dict['azimuth'][key][i]
           rel_time = timegrid[i] - reference_time
           if i  == 0:
             time_width = reference_time - timegrid[i] 
           else:
             time_width = timegrid[i] - timegrid[i-1]
           log.write("%s : %s %s %s %s %s %s %s %s\n" % (seq_no, ok, rel_time, time_width, el, az, stec, rm, vtec_factor))
           seq_no = seq_no + 1
         k = k + 1
         if use_mean:
           break
         log.write (' \n')
       log.close()
       print ('****** finished ionosphere predictions report: ', out_file)
    else:
      print ('*********** finished ionosphere predictions ***************')


    return big_dict