Source code for tesfdmtools.methods.Moptfilter

#!/usr/bin/env python3
#
'''
.. module:: Moptfilter
   :synopsis: Eventprofiles optimal filtering using multiple templates
.. moduleauthor:: Cor de Vries <c.p.de.vries@sron.nl>

'''

import os
import numpy

import matplotlib.pyplot as plt

from tesfdmtools.methods.IQrotate import IQphase,IQphrot
from tesfdmtools.utils.cu import cu

# ============================================================================================

def write_optfilter(templates,tnorms,hdf,channel,freq):
   '''
   write a file with the optimal filter data

   Args:
     *  `templates` = numpy array with template filter data
     *     `tnorms` = average amplitudes for the filters
     *    `hdf`     = the HDF5 object with the event data
     *    `channel` = channel used inthe HDF5 data
     *    `freq`    = frequency (pixel) data used in the HDF5 data
  
   '''
   bnam=os.path.basename(hdf.hdffile).rsplit('.',1)[0]
   fnam='MOptFilters_%s_ch%2.2d_px%2.2d.txt' % (bnam,channel,freq)
   olst=open(fnam,'w')
   olst.write("#Optimal multiple filter data\n")
   olst.write("#Inputfile: %s\n" % hdf.hdffile)
   olst.write("#Channel: %d\n" % channel)
   olst.write("#Freq: %d\n#\n" % freq)
   fmt='%17.8e'
   for i in numpy.arange(1,tnorms.size):
      fmt=fmt+' %17.8e'
   fmt=fmt+'\n'
   olst.write("#Filter scaling identifiers: \n")
   olst.write(fmt % tuple(tnorms))
   olst.write("#Templates: \n")
   for j in numpy.arange(templates[0,:].size):
      olst.write(fmt % tuple(templates[:,j]))
   olst.close()
   print("Templates filter file written: ",fnam)
   return

# ============================================================================================

[docs]def optfilter(hdf,channel,freq,indx,base1,base2,noisspec,debug=False,freqcutoff=None,\ rotate=False,risetime=False,bsec=0.05,absolute=False,prlen=None,apulsepos=None,\ wrtfilter=False,ntemplates=4,flip=False,**kwargs): ''' perform optimal filtering fit of individual pulses using multiple templates Args: * `hdf` = HDF5 input file object * `channel` = channel number being processed * `freq` = frequency number (pixel) being processed * `indx` = index of selected events, to be processed * `base1` = baseline level at start of record * `base2` = baseline level at end of record * `noisspec` = noise spectrum Kwargs: * `debug` = if True, plot various fit parameters [default: False] * `freqcutoff` = cutoff frequency (Hz) for optimal filtering [default: None] * `rotate` = rotation angle (radians) for I/Q pulse record * `risetime` = it True, compute rise time of pulses [default: None] * `bsec` = section of record to take for background (only used for 'rotate' or 'absolute') [default: 0.05] * `absolute` = use sqrt(I^2+Q^2) signal [default: False] * `prlen` = length of record to process (None = entire record) [default: None] * `apulsepos` = average position of pulse maximum; used for limited `prlen`. [default: None] * `wrtfilter` = write optimal filter templates to file, for further analysis * `ntemplates` = number of templates to use * `flip` = flip data in record Returns: * `ifit` = fitted pulse heigth parameters * `rtimes` = computed rise times of fitted pulses * `ftimes` = computed fall times of fitted pulses * `avpulse` = average pulse profile with baseline subtracted * `avbline` = average baseline for the average pulse prfile ''' print("Optimal filter, channel=",channel,' freq=',freq) print(" number of templates to use: %d" % ntemplates) aphase=0.0 if type(rotate) is bool: if rotate: aphase=getphase(hdf,channel,freq,indx,debug=debug) print("Optimal fit phase rotation: ",aphase) else: if type(rotate) is float: aphase=rotate print("Optimal fit phase rotation: ",aphase) sirecord=hdf.channel[channel].freq[freq][0][:,0] # read first record to get record parameters recp1=0 # use entire record recp2=sirecord.size if ( prlen is not None ) and ( apulsepos is not None ): # limit record length ? p1=int(apulsepos-100-bsec*sirecord.size) if p1 > 0: recp1=p1 p2=recp1+prlen if p2 < sirecord.size: recp2=p2 print("Optimal fit record length limited to: ",recp1,recp2) sirecord=sirecord[recp1:recp2] bl=int(bsec*sirecord.size) # section for background level samplerate=float(cu(hdf.channel[channel].freq[freq].attrs['sample_rate'])) # get sample rate if freqcutoff is None: slen=sirecord.size//2 # max samplingfrequency else: slen=int(float(freqcutoff)/float(samplerate)*sirecord.size) # frequency cutoff xax=numpy.arange(sirecord.size,dtype=float) # make x-axsis for record iax=numpy.arange(sirecord.size,dtype=int) bax=numpy.concatenate((iax[0:bl],iax[-bl:])) # baseline section fpulses=numpy.zeros((indx.size,(slen-1)),dtype=float) # initialize array to store pulse power spectra avpulse=numpy.zeros(sirecord.size,dtype=float) # average pulse profile if risetime: rtimes=numpy.empty(indx.size,dtype=float) # array of risetimes for events ftimes=numpy.empty(indx.size,dtype=float) # array of fall times for events else: rtimes=None ftimes=None amplitudes=numpy.empty(indx.size,dtype=float) # amplitudes of pulses for i,irec in enumerate(indx): # go through all records in selection list bas1=base1[irec] bas2=base2[irec] record=hdf.channel[channel].freq[freq][irec] if absolute: irecord=numpy.sqrt(record[:,0].astype(float)**2+record[:,1].astype(float)**2) else: if flip or ( record[0,0] < 0 ): # wrong rotation, rotate by pi irecord=-record[:,0] else: irecord=record[:,0] if aphase != 0.0: irecord,qrecord=IQphrot(record[:,0],record[:,1],aphase) irecord=irecord[recp1:recp2] # limit record length if absolute or ( aphase != 0.0 ): pp=numpy.polyfit(bax,irecord[bax],1) cirecord=irecord-(pp[0]*xax+pp[1]) else: cirecord=irecord-(bas1+xax/float(sirecord.size-1)*(bas2-bas1)) # retrieve I-signal and subtract background avpulse=avpulse+irecord # accumulate average pulse if risetime: rt,ft=getrisetime(xax,cirecord,debug=debug) # rise time in seconds rtimes[i]=rt/samplerate ftimes[i]=ft/samplerate fpulses[i,:]=numpy.absolute(numpy.fft.fft(cirecord)[1:slen]) # compute power spectrum # amplitudes[i]=fpulses[i,:].max() amplitudes[i]=fpulses[i,0] # power spectrum amplitude from first frequency if ( i % 1000 ) == 0: print("process record: ",irec) print("number of pulses processed: ",indx.size) avpulse=avpulse/float(indx.size) # average pulse bindx=numpy.concatenate((numpy.arange(100,dtype=int),numpy.arange((avpulse.size-100),avpulse.size,dtype=int))) abfit=numpy.polyfit(xax[bindx],avpulse[bindx],1) avpulse=avpulse-(abfit[0]*xax+abfit[1]) minav=numpy.argmin(avpulse) avbline=abfit[0]*minav+abfit[1] # average baseline nns=(noisspec**2)[1:slen] # noise spectrum normalisation # make multiple templates ampindx=numpy.argsort(amplitudes) # sort amplitudes fntemp=amplitudes.size/float(ntemplates) # number of amplitudes for one template templates=numpy.empty((ntemplates,(slen-1)),dtype=float) # to keep templates tempx=numpy.arange(ntemplates,dtype=float) # index coordinate for templates norms=numpy.empty(ntemplates) tnorms=numpy.empty(ntemplates) # templates normalization itx=0.0 ntref=ntemplates//2 for i in numpy.arange(ntemplates): it1=int(itx) itx=itx+fntemp it2=min(((int(itx)+1),indx.size)) tnorms[i]=numpy.mean(amplitudes[ampindx[it1:it2]]) # template scaling identifier templates[i,:]=numpy.mean(fpulses[ampindx[it1:it2],:],axis=0) # template norms[i]=numpy.sum((templates[i,:]**2)/nns) tfits=numpy.empty(ntemplates) tfits[0]=numpy.sum(templates[0,:]*templates[0,:]/nns)/norms[0] for i in numpy.arange(1,ntemplates): # factor of template with respect to previous tfits[i]=numpy.sum(templates[i,:]*templates[(i-1),:]/nns)/norms[(i-1)] for i in numpy.arange(2,ntemplates): # normalize factors with respect to first template tfits[i]=tfits[i]*tfits[i-1] tfits=tfits/tfits[ntref] # normalize with respect to reference for i in numpy.arange(ntemplates): # mutual normalisation of the templates templates[i,:]=templates[i,:]/tfits[i] norms[i]=numpy.sum((templates[i,:]**2)/nns) # if wrtfilter: # write the templates to file write_optfilter(templates,tnorms,hdf,channel,freq) # if debug: f, ax = plt.subplots(1) ax.set_yscale('log') ppx=numpy.arange(slen-1) for i in numpy.arange(ntemplates): ax.plot(ppx,templates[i,:]) ax.set_title('Templates') plt.show() plt.close('all') # ifit=numpy.zeros(indx.size,dtype=float) # initialize array to store optimal filter fit parameters nlast=ntemplates-1 for i in numpy.arange(indx.size): ccx=numpy.interp(amplitudes[i],tnorms,tempx) # interpolated coordinate for template icx=int(ccx) if ccx < 0.0: # coordinate before first template apulse=templates[0,:] # use first template norm=norms[0] # and first normalization elif ccx >= float(nlast): # coordinate beyond last template apulse=templates[nlast,:] # use last template norm=norms[nlast] # and last normalization else: apulse=templates[icx,:]+(ccx-icx)*(templates[(icx+1),:]-templates[icx,:]) # interpolated template norm=norms[icx]+(ccx-icx)*(norms[icx+1]-norms[icx]) # interpolated normalization # if ccx < 0.0: # coordinate before first template # icx=0 # extrapolate from first template # elif ccx >= float(nlast): # coordinate beyond last template # icx=nlast-2 # extrapolate from last template # apulse=templates[icx,:]+(ccx-icx)*(templates[(icx+1),:]-templates[icx,:]) # interpolated template # norm=norms[icx]+(ccx-icx)*(norms[icx+1]-norms[icx]) # interpolated normalization ifit[i]=numpy.sum(fpulses[i]*apulse/nns)/norm # compute optimal filter fit if debug: if risetime: np=3 else: np=2 f, ax = plt.subplots(np) nax=numpy.arange(indx.size) ax[1].plot(nax,ifit,'b.') ax[1].set_xlabel('event number') ax[1].set_ylabel('Pulse intensity') ax[0].set_title('Optimal filter fits') ax[0].hist(ifit,bins=500,histtype='stepfilled') ax[0].set_xlabel('Energy (arb. units)') ax[0].set_ylabel('Counts') if risetime: ax[2].hist(rtimes*1000,bins=512,align='mid') ax[2].set_xlabel("Rise time (ms)") ax[2].set_ylabel("N") ax[2].set_title("Pulse rise times") plt.show() plt.close('all') return (ifit,rtimes,ftimes,avpulse,avbline)