Source code for tesfdmtools.methods.TDoptfilter

#!/usr/bin/env python3
'''
.. module:: TDoptfilter
   :synopsis: Optimum filter fit of TES pulses in the time domain  
.. moduleauthor:: Cor de Vries <c.p.de.vries@sron.nl>

'''
import numpy

import matplotlib
import matplotlib.pyplot as plt

from tesfdmtools.methods.HDF_Eventutils import getrisetime,getphase
from tesfdmtools.methods.IQrotate import IQphase,IQphrot
from tesfdmtools.methods.shiftarr import shiftarr
from tesfdmtools.utils.cu import cu

[docs]def optfilter(hdf,channel,freq,indx,base1,base2,noisspec,debug=False,prlen=None,\ rotate=False,risetime=False,bsec=0.05,absolute=False,\ nppos=11,shiftpulse=False,flip=False,**kwargs): ''' perform optimal filtering fit of individual pulses (for time domain) 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: * `prlen` = record length to use (10% pre-max and 90% postmax) * `rotate` = rotate pulses to minimum Q [default: False] * `risetime` = if True, compute rise time of pulses [default: False] * `bsec` = section of record to take for background [default: 0.05] (only used for 'rotate' or 'absolute') * `absolute` = use sqrt(I^2+Q^2) signal [default: False] * `nppos` = number of pulse positions to consider for fitting * `shiftpulse` = if True, shift pulses to same position for pulse maximum * `flip` = flip data in record Returns: * `ifit` = fitted pulse heigth parameters * `rtimes` = computed rise times of fitted pulses ''' print("Optimal filter (time domain), channel=",channel,' freq=',freq) aphase=0.0 if type(rotate) is bool: if rotate: aphase=getphase(hdf,channel,freq,indx,debug=debug) else: if type(rotate) is float: aphase=rotate sirecord=hdf.channel[channel].freq[freq][indx[0]][:,0] # read first record to get record parameters if shiftpulse: print('Shift pulse maxima to identical position') pulsepos=numpy.argmin(sirecord) samplerate=float(cu(hdf.channel[channel].freq[freq].attrs['sample_rate'])) # get sample rate if prlen is None: c1=0 c2=sirecord.size # max samplingfrequency bl=int(bsec*(c2-c1)) # section for background level prlen=sirecord.size else: mm=numpy.argmin(sirecord) # frequency cutoff c1=max([0,int(mm-0.10*prlen)]) c2=c1+prlen if c2 > sirecord.size: c2=sirecord.size c1=max([0,int(c2-prlen)]) bl=int(bsec*(c2-c1)) # section for background level print("record size: ",sirecord.size," pulse peak at: ",mm) print(" use record from samples ",c1," to: ",c2) print(" background outside samples ",(c1+bl)," to: ",(c2-bl)) bl=int(bsec*(c2-c1)) # section for background level xax=numpy.arange(prlen,dtype=float) # make x-axsis for record iax=numpy.arange(prlen,dtype=int) bax=numpy.concatenate((iax[:bl],iax[-bl:])) # baseline section fpulses=numpy.zeros((indx.size,(c2-c1)),dtype=float) # initialize array to store pulse avpulse=numpy.zeros(prlen,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 for i,irec in enumerate(indx): # go through all record in selection list 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) if shiftpulse: pp=irecord.argmin() irecord=shiftarr(irecord,(pulsepos-pp)) irecord=irecord[c1:c2] pp=numpy.polyfit(bax.astype(float),irecord[bax].astype(float),1) cirecord=irecord-(pp[0]*xax+pp[1]) # subtract baseline # f,ax=plt.subplots(1) # ax.plot(xax[c1:c2],cirecord) # plt.show() # plt.close('all') 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,:]=cirecord 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 apulse=fpulses.sum(axis=0)/float(indx.size) # compute average pulse axax=numpy.arange(apulse.size,dtype=int) # bxax=numpy.concatenate((axax[:bl],axax[-bl:])) pp=numpy.polyfit(bxax.astype(float),apulse[bxax],1) apulse=-(apulse-(pp[0]*axax+pp[1])) # subtract baseline # print("apulse unfiltered surface: ",apulse.sum()) afft=numpy.fft.fft(apulse) # fft of template nfft=numpy.absolute(afft[0]) # magnitude of normalization # mfft=numpy.absolute(afft[afft.size//2]) # magnitude of highest frequency mfft=noisspec[-1] # extension to highest frequency for noise nnspec=numpy.concatenate((noisspec,[mfft],noisspec[-1:0:-1])) # add negative frequencies to noisespectrum nnspec[0]=nfft # fill zero frequency to prevent division by zero weight=numpy.real(numpy.fft.ifft(afft/(nnspec**2))) # filter template, using noise to get weights # print("apulse filtered surface: ",apulse.sum()) if debug: f, ax = plt.subplots(1) ax.plot(axax,weight,'b-') ax.set_xlabel('record bin') ax.set_ylabel('template weight') ax.set_title('noise-filtered template') plt.show() plt.close('all') # shift template to obtain fits as function of pulse position hna=nppos//2 weight[0:hna]=0.0 weight[-hna:]=0.0 nas=numpy.arange(nppos) weights=numpy.zeros((nppos,weight.size),dtype=float) for i in nas: # store for 'na' different positions ish=i-hna weights[i]=numpy.roll(weight,ish) norm=numpy.sum(apulse*weight) # average pulse weight normalization ifit=numpy.zeros(indx.size,dtype=float) # initialize array to store optimal filter fit parameters ishft=numpy.zeros(indx.size,dtype=float) ees=numpy.zeros(nppos) for i in numpy.arange(indx.size): for j in nas: ees[j]=numpy.sum(fpulses[i]*weights[j])/norm # compute for the different positions # print "ees: "+nppos*"%10.7f" % tuple(ees-ees.min()) pp=numpy.polyfit(nas.astype(float),ees,2) # fit polynomial to different shift results mee=pp[2]-(pp[1]**2/(4.0*pp[0])) # compute maximum of polynome ifit[i]=-mee # store maximum of fitted polynomial ishft[i]=-pp[1]/(2.0*pp[0]) # record fitshift for debug output if debug: f,ax = plt.subplots(1) ax.plot(ifit,ishft,'b.') ax.set_xlabel('optimal fit') ax.set_ylabel('opt. fit shift') ax.set_title('optimal fit shift') plt.show() plt.close('all') if risetime: np=4 else: np=3 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') ax[2].set_xlabel('record bin') ax[2].set_ylabel('TD filter') ax[2].plot(axax,apulse,'b-') ax[2].plot(axax[:bl],apulse[:bl],'r-',axax[-bl:],apulse[-bl:],'r-') if risetime: ax[3].hist(rtimes*1000,bins=512,align='mid') ax[3].set_xlabel("Rise time (ms)") ax[3].set_ylabel("N") ax[3].set_title("Pulse rise times") plt.show() plt.close('all') return (ifit,rtimes,ftimes,avpulse,avbline)