コード例 #1
0
def test():
    nx=17
    DataTrue=np.zeros((1,1,nx,nx),np.float32)
    DataTrue[0,0,nx/2,nx/2]=1.
    DataPSF=DataTrue.copy()
    PSF=ModFFTW.ConvolveGaussian(DataPSF,CellSizeRad=1,GaussPars=[(1.,1.,0.)])

    DataTrue.fill(0)
    DataTrue[0,0,nx/2,nx/2]=1.
    DataTrue[0,0,nx/2+5,nx/2+4]=1.
    #DataTrue[0,0,nx/2,nx/2]=1.
    DataTrue=ModFFTW.ConvolveGaussian(DataTrue,CellSizeRad=1,GaussPars=[(1,.5,0.)])
    #DataTrue=np.random.randn(*DataTrue.shape)

    DataTrue[0,0,nx/2-5,nx/2+4]+=2.
    DataTrue[0,0,nx/2-2,nx/2+2]+=2.
    # DataTrue+=np.random.randn(*DataTrue.shape)*0.05

    Dirty=ModFFTW.ConvolveGaussian(DataTrue,CellSizeRad=1,GaussPars=[(1.,1.,0.)])
    #DataConv=ModFFTW.ConvolveGaussian(DataTrue,CellSizeRad=1,GaussPars=[(1.,1.,0.)])
    #DataConv=DataTrue
    #IndDataTrue=ArrayToInd(DataConv)
    FreqsInfo=None

    _,_,indx,indy=np.where(DataTrue>1e-1)
    ListPixParms=[ij for ij in zip(indx,indy)]

    _,_,indx,indy=np.where(Dirty>1e-1)
    ListPixData=[ij for ij in zip(indx,indy)]

    CEv=ClassEvolveGA(Dirty,PSF,FreqsInfo,ListPixData=ListPixData,ListPixParms=ListPixParms)
    CEv.ArrayMethodsMachine.DataTrue=DataTrue


    return CEv
コード例 #2
0
ファイル: TestFitter.py プロジェクト: dodsonicrar/DDFacet
 def restoreFittedBeam(rot):
     imgSize = 256
     cellSize = np.deg2rad(4./3600.)
     params = (10, 5, rot) #maj, min, theta
     #create input with code borrowed from Tigger:
     xx,yy = np.meshgrid(np.arange(0,imgSize),np.arange(0,imgSize))
     inp = gauss2d([1,imgSize/2,imgSize/2,params[1],params[0],params[2]],circle=0,rotate=1,vheight=0)(xx,yy)
     inp = inp.reshape(1,1,imgSize,imgSize)
     #fit
     fittedParams = tuple((fitter.FitCleanBeam(inp[0, 0, :, :]) *
                           np.array([cellSize, cellSize, 1])).tolist())
     #restore fitted clean beam with an FFT convolution:
     delta = np.zeros([1, 1, imgSize, imgSize])
     delta[0, 0, imgSize // 2, imgSize // 2] = 1
     rest, _ = fftconvolve.ConvolveGaussianScipy(delta,
                                              Sig=5,
                                              GaussPar=fittedParams)
     
     rest = fftconvolve.ConvolveGaussian(shareddict={"in":delta,
                                                     "out":delta},
                                                     field_in="in",
                                                     field_out="out",
                                          ch=0,
                                          CellSizeRad=cellSize,
                                          GaussPars_ch=fittedParams,
                                          Normalise=False)
                                          
     assert np.allclose(inp, rest, rtol=1e-2, atol=1e-2)
コード例 #3
0
def testMF():
    nx=17

    nf=2
    nu=np.linspace(100,200,nf)*1e6
    FreqsInfo=None
    FreqsInfo={"freqs":[nu[0:1],nu[1:2]],"WeightChansImages":np.array([0.5, 0.5])}

    # nf=1
    # nu=np.linspace(100,200,nf)*1e6
    # FreqsInfo=None

    PSF=np.zeros((nf,1,nx,nx),np.float32)
    PSF[:,0,nx/2,nx/2]=1.
    PSF=ModFFTW.ConvolveGaussian(PSF,CellSizeRad=1,GaussPars=[(1.,1.,0.)]*nf)

    DataModel=np.zeros((1,1,nx,nx),np.float32)
    Alpha=np.zeros((1,1,nx,nx),np.float32)

    DataModel[0,0,nx/2,nx/2]=1.
    #Alpha[0,0,:,:]=-.8

    #DataModel[0,0,nx/2+5,nx/2+4]=1.
    DataModel=ModFFTW.ConvolveGaussian(DataModel,CellSizeRad=1,GaussPars=[(1,.5,0.)])
    #Alpha[0,0,nx/2,nx/2]=-.8

    DataModel[0,0,nx/2,nx/2]=+1.
    Alpha[0,0,nx/2,nx/2]=.8
    DataModel[0,0,nx/2-5,nx/2+4]+=2.
    #DataModel[0,0,nx/2-2,nx/2+2]+=2.
    Alpha[0,0,nx/2-5,nx/2+4]=-.8

    FreqRef=np.mean(nu)
    nur=nu.reshape((2,1,1,1))
    DataModelMF=DataModel*(nur/FreqRef)**Alpha

    Dirty=ModFFTW.ConvolveGaussian(DataModelMF,CellSizeRad=1,GaussPars=[(1.,1.,0.)]*nf)

    #DataConv=ModFFTW.ConvolveGaussian(DataTrue,CellSizeRad=1,GaussPars=[(1.,1.,0.)])
    #DataConv=DataTrue
    #IndDataTrue=ArrayToInd(DataConv)

    indx,indy=np.where(Dirty[0,0]>1e-1)
    ListPixParms=[ij for ij in zip(indx,indy)]
    indx,indy=np.where(Dirty[0,0]>1e-2)
    ListPixParms=[ij for ij in zip(indx,indy)]
    ListPixData=ListPixParms

    GD={"GAClean":{"GASolvePars":["S","Alpha"]}}


    CEv=ClassEvolveGA(Dirty,PSF,FreqsInfo,ListPixParms=ListPixParms,ListPixData=ListPixData,GD=GD)
    CEv.ArrayMethodsMachine.DataTrue=DataModelMF
    CEv.ArrayMethodsMachine.PM.DicoIParm["S"]["DataModel"]=DataModel


    return CEv
コード例 #4
0
    def GiveSpectralIndexMap(self, CellSizeRad=1., GaussPars=[(1, 1, 0)], DoConv=True, MaxSpi=100, MaxDR=1e+6,
                             threshold=None):
        dFreq = 1e6
        # f0=self.DicoSMStacked["AllFreqs"].min()
        # f1=self.DicoSMStacked["AllFreqs"].max()
        RefFreq = self.DicoSMStacked["RefFreq"]
        f0 = RefFreq / 1.5
        f1 = RefFreq * 1.5

        M0 = self.GiveModelImage(f0)
        M1 = self.GiveModelImage(f1)
        if DoConv:
            # M0=ModFFTW.ConvolveGaussian(M0,CellSizeRad=CellSizeRad,GaussPars=GaussPars)
            # M1=ModFFTW.ConvolveGaussian(M1,CellSizeRad=CellSizeRad,GaussPars=GaussPars)
            # M0,_=ModFFTW.ConvolveGaussianWrapper(M0,Sig=GaussPars[0][0]/CellSizeRad)
            # M1,_=ModFFTW.ConvolveGaussianWrapper(M1,Sig=GaussPars[0][0]/CellSizeRad)
            M0, _ = ModFFTW.ConvolveGaussianScipy(M0, Sig=GaussPars[0][0] / CellSizeRad)
            M1, _ = ModFFTW.ConvolveGaussianScipy(M1, Sig=GaussPars[0][0] / CellSizeRad)

        # print M0.shape,M1.shape
        # compute threshold for alpha computation by rounding DR threshold to .1 digits (i.e. 1.65e-6 rounds to 1.7e-6)
        if threshold is not None:
            minmod = threshold
        elif not np.all(M0 == 0):
            minmod = float("%.1e" % (np.max(np.abs(M0)) / MaxDR))
        else:
            minmod = 1e-6

        # mask out pixels above threshold
        mask = (M1 < minmod) | (M0 < minmod)
        print("computing alpha map for model pixels above %.1e Jy (based on max DR setting of %g)" % (
              minmod, MaxDR), file=log)
        M0[mask] = minmod
        M1[mask] = minmod
        # with np.errstate(invalid='ignore'):
        #    alpha = (np.log(M0)-np.log(M1))/(np.log(f0/f1))
        # print
        # print np.min(M0),np.min(M1),minmod
        # print
        alpha = (np.log(M0) - np.log(M1)) / (np.log(f0 / f1))
        alpha[mask] = 0

        # mask out |alpha|>MaxSpi. These are not physically meaningful anyway
        mask = alpha > MaxSpi
        alpha[mask] = MaxSpi
        masked = mask.any()
        mask = alpha < -MaxSpi
        alpha[mask] = -MaxSpi
        if masked or mask.any():
            print(ModColor.Str("WARNING: some alpha pixels outside +/-%g. Masking them." % MaxSpi, col="red"), file=log)
        return alpha
コード例 #5
0
    def GiveSpectralIndexMap(self,
                             CellSizeRad=1.,
                             GaussPars=[(1, 1, 0)],
                             DoConv=True,
                             MaxSpi=100,
                             MaxDR=1e+6,
                             threshold=None):

        dFreq = 1e6
        RefFreq = self.DicoSMStacked["RefFreq"]
        f0 = RefFreq / 1.5  #self.DicoSMStacked["AllFreqs"].min()
        f1 = RefFreq * 1.5  #self.DicoSMStacked["AllFreqs"].max()
        M0 = self.GiveModelImage(f0)
        M1 = self.GiveModelImage(f1)
        if DoConv:
            #M0=ModFFTW.ConvolveGaussian(M0,CellSizeRad=CellSizeRad,GaussPars=GaussPars)
            #M1=ModFFTW.ConvolveGaussian(M1,CellSizeRad=CellSizeRad,GaussPars=GaussPars)
            #M0,_=ModFFTW.ConvolveGaussianWrapper(M0,Sig=GaussPars[0][0]/CellSizeRad)
            #M1,_=ModFFTW.ConvolveGaussianWrapper(M1,Sig=GaussPars[0][0]/CellSizeRad)
            M0, _ = ModFFTW.ConvolveGaussianScipy(M0,
                                                  Sig=GaussPars[0][0] /
                                                  CellSizeRad)
            M1, _ = ModFFTW.ConvolveGaussianScipy(M1,
                                                  Sig=GaussPars[0][0] /
                                                  CellSizeRad)

        # compute threshold for alpha computation by rounding DR threshold to .1 digits (i.e. 1.65e-6 rounds to 1.7e-6)
        if threshold is not None:
            minmod = threshold
        elif not np.all(M0 == 0):
            minmod = float("%.1e" % (np.max(np.abs(M0)) / MaxDR))
        else:
            minmod = 1e-6

        # mask out pixels above threshold
        mask = (M1 < minmod) | (M0 < minmod)
        print >> log, "computing alpha map for model pixels above %.1e Jy (based on max DR setting of %g)" % (
            minmod, MaxDR)
        M0[mask] = minmod
        M1[mask] = minmod
        alpha = (np.log(M0) - np.log(M1)) / (np.log(f0 / f1))
        alpha[mask] = 0

        # Np=1000
        # indx,indy=np.int64(np.random.rand(Np)*M0.shape[0]),np.int64(np.random.rand(Np)*M0.shape[1])
        # med=np.median(np.abs(M0[:,:,indx,indy]))
        # Mask=((M1>100*med)&(M0>100*med))
        # alpha=np.zeros_like(M0)
        # alpha[Mask]=(np.log(M0[Mask])-np.log(M1[Mask]))/(np.log(f0/f1))
        return alpha
コード例 #6
0
ファイル: ClassDDEGridMachine.py プロジェクト: amisk/DDFacet
    def _getGlobalFFTWMachine(FFTMachineType, GridShape, dtype):
        """Returns an FFTWMachine matching the arguments.
        Makes sure an FFTW machine is initialized only once per process, and only as needed.
        """
        machine = ClassDDEGridMachine._global_fftw_machines.get(
            (GridShape, dtype))
        if machine is None:
            if FFTMachineType == "FFTW":
                # use single-core FFT because we parallelize by facet instead
                ClassDDEGridMachine._global_fftw_machines[(
                    GridShape,
                    dtype)] = machine = ModFFTW.FFTW_2Donly(GridShape,
                                                            dtype,
                                                            ncores=1)
            elif FFTMachineType == "LAPACK":
                ClassDDEGridMachine._global_fftw_machines[(
                    GridShape, dtype)] = machine = ModFFTW.FFTW_2Donly_np(
                        GridShape, dtype)

        return machine
コード例 #7
0
ファイル: ClassImToGrid.py プロジェクト: Chanka2019/DDFacet-1
    def __init__(self,
                 GridShape=None,
                 PaddingInnerCoord=None,
                 OverS=None,
                 Padding=None,
                 dtype=None,
                 ifzfCF=None,
                 Mode="Blender",
                 GD=None):

        self.GridShape = GridShape
        self.PaddingInnerCoord = PaddingInnerCoord
        self.OverS = OverS
        self.Padding = Padding
        self.dtype = dtype
        self.ifzfCF = ifzfCF
        self.GD = GD
        self.FFTWMachine = ModFFTW.FFTW_2Donly_np(self.GridShape,
                                                  self.dtype,
                                                  ncores=1)
        self.Mode = Mode
コード例 #8
0
ファイル: Restore.py プロジェクト: dodsonicrar/DDFacet
    def GiveRandomModelIm(self):
#        np.random.seed(0)
        SModel,NModel=np.load(self.options.RandomCat_CountsFile).T
        ind=np.argsort(SModel)
        SModel=SModel[ind]
        NModel=NModel[ind]
        #SModel/=1e3
        NModel/=SModel**(5/2.)
        def GiveNPerOmega(s):
            xp=np.interp(np.log10(s), np.log10(SModel), np.log10(NModel), left=None, right=None)
            # import pylab
            # pylab.clf()
            # pylab.plot(np.log10(SModel), np.log10(NModel))
            # pylab.scatter(np.log10(s),xp)
            # pylab.draw()
            # pylab.show()
            # pylab.pause(0.1)
            return 10**xp

        std=np.std(self.Residual.flat[np.int64(np.random.rand(1000)*self.Residual.size)])
        nbin=10000
        smin=2.*std
        smax=10.
        LogS=np.linspace(np.log10(smin),np.log10(smax),nbin)

        Model=np.zeros_like(self.Residual)
        Omega=self.Residual.size*self.CellSizeRad**2
        nx=Model.shape[-1]
        im=image(self.FitsFile)
        Lra=[]
        Ldec=[]
        LS=[]
        SRA=[]
        SDEC=[]
        
        f,p,_,_=im.toworld((0,0,0,0))
        for iBin in range(nbin-1):
            ThisS=(10**LogS[iBin]+10**LogS[iBin+1])/2.
            dx=10**LogS[iBin+1]-10**LogS[iBin]
            n=int(scipy.stats.poisson.rvs(GiveNPerOmega(ThisS)*Omega*dx))#int(round(GiveNPerOmega(ThisS)*Omega*dx))
            indx=np.array([np.int64(np.random.rand(n)*nx)]).ravel()
            indy=np.array([np.int64(np.random.rand(n)*nx)]).ravel()
            s0,s1=10**LogS[iBin],10**LogS[iBin+1]
            RandS=np.random.rand(n)*(s1-s0)+s0
            Model[0,0,indy,indx]=RandS
            for iS in range(indx.size):
                _,_,dec,ra=im.toworld((0,0,indy[iS],indx[iS]))
                Lra.append(ra)
                Ldec.append(dec)
                LS.append(RandS[iS])
                #SRA.append(rad2hmsdms(ra,Type="ra").replace(" ",":"))
                #SDEC.append(rad2hmsdms(dec,Type="dec").replace(" ",":"))

        #Cat=np.zeros((len(Lra),),dtype=[("ra",np.float64),("StrRA","S200"),("dec",np.float64),("StrDEC","S200"),("S",np.float64)])
        Cat=np.zeros((len(Lra),),dtype=[("ra",np.float64),("dec",np.float64),("S",np.float64)])
        Cat=Cat.view(np.recarray)
        Cat.ra=np.array(Lra)
        Cat.dec=np.array(Ldec)
        #Cat.StrRA=np.array(SRA)
        #Cat.StrDEC=np.array(SDEC)
        Cat.S=np.array(LS)
        CatName="%s.cat.npy"%self.OutName
        print("Saving simulated catalog as %s"%CatName, file=log)
        np.save(CatName,Cat)

        ModelOut=np.zeros_like(Model)
        ModelOut[0,0]=Model[0,0].T[::-1]
        
        p=self.options.RandomCat_TotalToPeak
        if p>1.:
            nx=101
            x,y=np.mgrid[-nx:nx+1,-nx:nx+1]
            r2=x**2+y**2
            def G(sig):
                C0=1./(2.*np.pi*sig**2)
                C=C0*np.exp(-r2/(2.*sig**2))
                C/=np.sum(C)
                return C
            ListSig=np.linspace(0.001,10.,100)
            TotToPeak=np.array([1./np.max(G(s)) for s in ListSig])
            sig=np.interp(self.options.RandomCat_TotalToPeak,TotToPeak,ListSig)
            print("Found a sig of %f"%sig, file=log)
            Gaussian=G(sig)
            ModelOut[0,0]=scipy.signal.fftconvolve(ModelOut[0,0], G(sig), mode='same')

            FWHMFact=2.*np.sqrt(2.*np.log(2.))
            BeamPix=self.BeamPix/FWHMFact
            Model=G(sig).reshape((1,1,x.shape[0],x.shape[0]))
            ConvModel,_=ModFFTW.ConvolveGaussianWrapper(Model,Sig=BeamPix)
            self.SimulObsPeak=np.max(ConvModel)
            print("  Gaussian Peak: %f"%np.max(Gaussian), file=log)
            print("  Gaussian Int : %f"%np.sum(Gaussian), file=log)
            print("  Obs peak     : %f"%self.SimulObsPeak, file=log)
            self.header_dict["OPKRATIO"]=self.SimulObsPeak
            self.header_dict["GSIGMA"]=sig
            self.header_dict["RTOTPK"]=self.options.RandomCat_TotalToPeak
        

        else:
            self.header_dict["OPKRATIO"]=1.
            self.header_dict["GSIGMA"]=0.
            self.header_dict["RTOTPK"]=1.

        
        return ModelOut
コード例 #9
0
ファイル: Restore.py プロジェクト: dodsonicrar/DDFacet
    def Restore(self):
        print("Create restored image", file=log)





        
        FWHMFact=2.*np.sqrt(2.*np.log(2.))
        FWHMFact=2.*np.sqrt(2.*np.log(2.))

        BeamPix=self.BeamPix/FWHMFact
        sigma_x, sigma_y=BeamPix,BeamPix
        theta=0.
        bmaj=np.max([sigma_x, sigma_y])*self.CellArcSec*FWHMFact
        bmin=np.min([sigma_x, sigma_y])*self.CellArcSec*FWHMFact

        #bmaj=bmin=0.001666666666666667*3600
        #sigma_x=
        self.FWHMBeam=(bmaj/3600./np.sqrt(2.),bmin/3600./np.sqrt(2.),theta)
        self.PSFGaussPars = (sigma_x*self.CellSizeRad, sigma_y*self.CellSizeRad, theta)

        #print "!!!!!!!!!!!!!!!!!!!!"
        #self.PSFGaussPars = (BeamPix,BeamPix,0)



        RefFreq=self.ModelMachine.RefFreq
        df=RefFreq*0.5

        # ################################"


        if self.options.PSFCache!="":

            import os
            IdSharedMem=str(int(os.getpid()))+"."
            MeanModelImage=self.ModelMachine.GiveModelImage(RefFreq)

            # #imNorm=image("6SBc.KAFCA.restoredNew.fits.6SBc.KAFCA.restoredNew.fits.MaskLarge.fits").getdata()
            # imNorm=image("6SB.KAFCA.GA.BIC_00.AP.dirty.fits.mask.fits").getdata()
            # MASK=np.zeros_like(imNorm)
            # nchan,npol,_,_=MASK.shape
            # for ch in range(nchan):
            #     for pol in range(npol):
            #         MASK[ch,pol,:,:]=imNorm[ch,pol,:,:].T[::-1,:]
            # MeanModelImage[MASK==0]=0

            # MeanModelImage.fill(0)
            # MeanModelImage[0,0,100,100]=1


            from DDFacet.Imager.GA import ClassSmearSM
            from DDFacet.Imager import ClassPSFServer
            self.DicoVariablePSF = MyPickle.FileToDicoNP(self.options.PSFCache)
            
            self.PSFServer=ClassPSFServer.ClassPSFServer()
            
            self.PSFServer.setDicoVariablePSF(self.DicoVariablePSF,NormalisePSF=True)
            #return self.Residual,MeanModelImage,self.PSFServer


            # CasaImage=ClassCasaImage.ClassCasaimage("Model.fits",MeanModelImage.shape,self.Cell,self.radec)#Lambda=(Lambda0,dLambda,self.NBands))
            # CasaImage.setdata(MeanModelImage,CorrT=True)
            # CasaImage.ToFits()
            # #CasaImage.setBeam((SmoothFWHM,SmoothFWHM,0))
            # CasaImage.close()


            SmearMachine=ClassSmearSM.ClassSmearSM(self.Residual,
                                                   MeanModelImage*self.SqrtNormImage,
                                                   self.PSFServer,
                                                   DeltaChi2=4.,
                                                   IdSharedMem=IdSharedMem,
                                                   NCPU=self.options.NCPU)
            SmearedModel=SmearMachine.Smear()
            SmoothFWHM=self.CellArcSec*SmearMachine.RestoreFWHM/3600.
            ModelSmearImage="%s.RestoredSmear"%self.BaseImageName
            CasaImage=ClassCasaImage.ClassCasaimage(ModelSmearImage,SmearedModel.shape,self.Cell,self.radec)#Lambda=(Lambda0,dLambda,self.NBands))
            CasaImage.setdata(SmearedModel+self.Residual,CorrT=True)
            #CasaImage.setdata(SmearedModel,CorrT=True)
            CasaImage.setBeam((SmoothFWHM,SmoothFWHM,0))
            CasaImage.ToFits()
            CasaImage.close()
            SmearMachine.CleanUpSHM()
            stop

        # ################################"
        #self.ModelMachine.ListScales[0]["Alpha"]=-0.8

        # model image
        #ModelMachine.GiveModelImage(RefFreq)

        FEdge=np.linspace(RefFreq-df,RefFreq+df,self.NBands+1)
        FCenter=(FEdge[0:-1]+FEdge[1::])/2.
        C=299792458.
        Lambda0=C/FCenter[-1]
        dLambda=1
        if self.NBands>1:
            dLambda=np.abs(C/FCenter[0]-C/FCenter[1])

        ListRestoredIm=[]
        Lambda=[Lambda0+i*dLambda for i in range(self.NBands)]
        ListRestoredImCorr=[]
        ListModelIm=[]
        #print C/np.array(Lambda)
        # restored image

        for l in Lambda:
            freq=C/l
            
            if self.options.RandomCat:
                print("Create random catalog... ", file=log)
                ModelImage=self.GiveRandomModelIm()
            else:
                print("Get ModelImage... ", file=log)
                ModelImage=self.ModelMachine.GiveModelImage(freq)
            
            if self.options.ZeroNegComp:
                print("Zeroing negative componants... ", file=log)
                ModelImage[ModelImage<0]=0
            ListModelIm.append(ModelImage)


            if self.options.Mode=="App":
                print("  ModelImage to apparent flux... ", file=log)
                ModelImage=ModelImage*self.SqrtNormImage
            print("Convolve... ", file=log)
            print("   MinMax = [%f , %f] @ freq = %f MHz"%(ModelImage.min(),ModelImage.max(),freq/1e6), file=log)
            #RestoredImage=ModFFTW.ConvolveGaussianScipy(ModelImage,CellSizeRad=self.CellSizeRad,GaussPars=[self.PSFGaussPars])

            
            if self.options.AddNoise>0.:
                print("Adding Noise... ", file=log)
                ModelImage+=np.random.randn(*ModelImage.shape)*self.options.AddNoise

            RestoredImage,_=ModFFTW.ConvolveGaussianWrapper(ModelImage,Sig=BeamPix)
# =======
#             #RestoredImage,_=ModFFTW.ConvolveGaussianWrapper(ModelImage,Sig=BeamPix)

#             def GiveGauss(Sig0,Sig1):
#                 npix=20*int(np.sqrt(Sig0**2+Sig1**2))
#                 if not npix%2: npix+=1
#                 dx=npix/2
#                 x,y=np.mgrid[-dx:dx:npix*1j,-dx:dx:npix*1j]
#                 dsq=x**2+y**2
#                 return Sig0**2/(Sig0**2+Sig1**2)*np.exp(-dsq/(2.*(Sig0**2+Sig1**2)))
#             R2=np.zeros_like(ModelImage)

#             Sig0=BeamPix/np.sqrt(2.)
#             if self.options.RandomCat:
#                 Sig1=(self.options.RandomCat_SigFactor-1.)*Sig0
#             else:
#                 Sig1=0.
#             nch,npol,_,_=ModelImage.shape
#             for ch in range(nch):
#                 in1=ModelImage[ch,0]
#                 R2[ch,0,:,:]=scipy.signal.fftconvolve(in1,GiveGauss(Sig0,Sig1), mode='same').real
#             RestoredImage=R2

#             self.header_dict["GSIGMA"]=Sig0


#             # print np.max(np.abs(R2-RestoredImage))
#             # import pylab
#             # ax=pylab.subplot(1,3,1)
#             # pylab.imshow(RestoredImage[0,0],interpolation="nearest")
#             # pylab.colorbar()
#             # pylab.subplot(1,3,2,sharex=ax,sharey=ax)
#             # pylab.imshow(R2[0,0],interpolation="nearest")
#             # pylab.colorbar()
#             # pylab.subplot(1,3,3,sharex=ax,sharey=ax)
#             # pylab.imshow((RestoredImage-R2)[0,0],interpolation="nearest")
#             # pylab.colorbar()
#             # pylab.show()
#             # stop

# >>>>>>> 0457182a873da89a2758f4be8a18f55cefd88e44

            RestoredImageRes=RestoredImage+self.Residual
            ListRestoredIm.append(RestoredImageRes)
            RestoredImageResCorr=RestoredImageRes/self.SqrtNormImage
            ListRestoredImCorr.append(RestoredImageResCorr)

        #print FEdge,FCenter

        print("Save... ", file=log)
        _,_,nx,_=RestoredImageRes.shape
        RestoredImageRes=np.array(ListRestoredIm).reshape((self.NBands,1,nx,nx))
        RestoredImageResCorr=np.array(ListRestoredImCorr).reshape((self.NBands,1,nx,nx))

        ModelImage=np.array(ListModelIm).reshape((self.NBands,1,nx,nx))
        


        if self.OutName=="":
            ImageName="%s.restoredNew"%self.BaseImageName
            ImageNameCorr="%s.restoredNew.corr"%self.BaseImageName
            ImageNameModel="%s.model"%self.BaseImageName
            ImageNameModelConv="%s.modelConv"%self.BaseImageName
        else:
            ImageName=self.OutName
            ImageNameCorr=self.OutName+".corr"
            ImageNameModel="%s.model"%self.OutName
            ImageNameModelConv="%s.modelConv"%self.OutName

        CasaImage=ClassCasaImage.ClassCasaimage(ImageNameModel,RestoredImageRes.shape,self.Cell,self.radec,header_dict=self.header_dict)#Lambda=(Lambda0,dLambda,self.NBands))
        CasaImage.setdata(ModelImage,CorrT=True)
        CasaImage.setBeam(self.FWHMBeam)
        CasaImage.ToFits()
        CasaImage.close()

        CasaImage=ClassCasaImage.ClassCasaimage(ImageName,RestoredImageRes.shape,self.Cell,self.radec,Freqs=C/np.array(Lambda).ravel(),header_dict=self.header_dict)#,Lambda=(Lambda0,dLambda,self.NBands))
        CasaImage.setdata(RestoredImageRes,CorrT=True)
        CasaImage.setBeam(self.FWHMBeam)
        CasaImage.ToFits()
        CasaImage.close()
        
        CasaImage=ClassCasaImage.ClassCasaimage(ImageNameModelConv,RestoredImage.shape,self.Cell,self.radec,Freqs=C/np.array(Lambda).ravel(),header_dict=self.header_dict)#,Lambda=(Lambda0,dLambda,self.NBands))
        CasaImage.setdata(RestoredImage,CorrT=True)
        CasaImage.setBeam(self.FWHMBeam)
        CasaImage.ToFits()
        CasaImage.close()

        if self.MakeCorrected:
            CasaImage=ClassCasaImage.ClassCasaimage(ImageNameCorr,RestoredImageResCorr.shape,self.Cell,self.radec,Freqs=C/np.array(Lambda).ravel(),header_dict=self.header_dict)#,Lambda=(Lambda0,dLambda,self.NBands))
            CasaImage.setdata(RestoredImageResCorr,CorrT=True)
            CasaImage.setBeam(self.FWHMBeam)
            CasaImage.ToFits()
            CasaImage.close()
        

        # ImageName="%s.modelConv"%self.BaseImageName
        # CasaImage=ClassCasaImage.ClassCasaimage(ImageName,ModelImage.shape,self.Cell,self.radec)
        # CasaImage.setdata(self.RestoredImage,CorrT=True)
        # CasaImage.ToFits()
        # CasaImage.setBeam(self.FWHMBeam)
        # CasaImage.close()


        # Alpha image
        if self.DoAlpha:
            print("Get Index Map... ", file=log)
            IndexMap=self.ModelMachine.GiveSpectralIndexMap(CellSizeRad=self.CellSizeRad,GaussPars=[self.PSFGaussPars])
            ImageName="%s.alphaNew"%self.BaseImageName
            print("  Save... ", file=log)
            CasaImage=ClassCasaImage.ClassCasaimage(ImageName,ModelImage.shape,self.Cell,self.radec)
            CasaImage.setdata(IndexMap,CorrT=True)
            CasaImage.ToFits()
            CasaImage.close()
            print("  Done. ", file=log)
コード例 #10
0
    def GiveSpectralIndexMap(self, GaussPars=[(1, 1, 0)], ResidCube=None,
                             GiveComponents=False, ChannelWeights=None):

        # convert to radians
        ex, ey, pa = GaussPars
        ex *= np.pi/180/np.sqrt(2)/2
        ey *= np.pi/180/np.sqrt(2)/2
        epar = (ex + ey)/2.0
        pa = 0.0

        # get in terms of number of cells
        CellSizeRad = self.GD['Image']['Cell'] * np.pi / 648000

        # get Gaussian kernel
        GaussKern = ModFFTW.GiveGauss(self.Npix, CellSizeRad=CellSizeRad, GaussPars=(epar, epar, pa), parallel=False)

        # take FT
        Fs = np.fft.fftshift
        iFs = np.fft.ifftshift

        # evaluate model
        ModelImage = self.GiveModelImage(self.GridFreqs)

        # pad GausKern and take FT
        GaussKern = np.pad(GaussKern, self.Npad, mode='constant')
        FTshape, _ = GaussKern.shape
        from scipy import fftpack as FT
        GaussKernhat = FT.fft2(iFs(GaussKern))

        # pad and FT of ModelImage
        ModelImagehat = np.zeros((self.Nchan, FTshape, FTshape), dtype=np.complex128)
        ConvModelImage = np.zeros((self.Nchan, self.Npix, self.Npix), dtype=np.float64)
        I = slice(self.Npad, -self.Npad)
        for i in range(self.Nchan):
            tmp_array = np.pad(ModelImage[i, 0], self.Npad, mode='constant')
            ModelImagehat[i] = FT.fft2(iFs(tmp_array)) * GaussKernhat
            ConvModelImage[i] = Fs(FT.ifft2(ModelImagehat[i]))[I, I].real

        if ResidCube is not None:
            ConvModelImage += ResidCube.squeeze()
            RMS = np.std(ResidCube.flatten())
            Threshold = self.GD["SPIMaps"]["AlphaThreshold"] * RMS
        else:
            AbsModel = np.abs(ModelImage).squeeze()
            MinAbsImage = np.amin(AbsModel, axis=0)
            RMS = np.min(np.abs(MinAbsImage.flatten())) # base cutoff on smallest value in model
            Threshold = self.GD["SPIMaps"]["AlphaThreshold"] * RMS

        # get minimum along any freq axis
        MinImage = np.amin(ConvModelImage, axis=0)
        MaskIndices = np.argwhere(MinImage > Threshold)
        FitCube = ConvModelImage[:, MaskIndices[:, 0], MaskIndices[:, 1]]


        if ChannelWeights is None:
            weights = np.ones(self.Nchan, dtype=np.float32)
        else:
            weights = ChannelWeights.astype(np.float32)
            if ChannelWeights.size != self.Nchan:
                import warnings
                warnings.warn("The provided channel weights are of incorrect length. Ignoring weights.", RuntimeWarning)
                weights = np.ones(self.Nchan, dtype=np.float32)

        try:
            import traceback
            from africanus.model.spi.dask import fit_spi_components
            NCPU = self.GD["Parallel"]["NCPU"]
            if NCPU:
                from multiprocessing.pool import ThreadPool
                import dask

                dask.config.set(pool=ThreadPool(NCPU))
            else:
                import multiprocessing
                NCPU = multiprocessing.cpu_count()

            import dask.array as da
            _, ncomps = FitCube.shape
            FitCubeDask = da.from_array(FitCube.T.astype(np.float64), chunks=(ncomps//NCPU, self.Nchan))
            weightsDask = da.from_array(weights.astype(np.float64), chunks=(self.Nchan))
            freqsDask = da.from_array(np.array(self.GridFreqs).astype(np.float64), chunks=(self.Nchan))

            alpha, varalpha, Iref, varIref = fit_spi_components(FitCubeDask, weightsDask,
                                                                freqsDask, self.RefFreq,
                                                                dtype=np.float64).compute()
        except Exception as e:
            traceback_str = traceback.format_exc(e)
            print("Warning - Failed at importing africanus spi fitter. This could be an issue with the dask " \
                        "version. Falling back to (slow) scipy version", file=log)
            print("Original traceback - ", traceback_str, file=log)
            alpha, varalpha, Iref, varIref = self.FreqMachine.FitSPIComponents(FitCube, self.GridFreqs, self.RefFreq)

        _, _, nx, ny = ModelImage.shape
        alphamap = np.zeros([nx, ny])
        Irefmap = np.zeros([nx, ny])
        alphastdmap = np.zeros([nx, ny])
        Irefstdmap = np.zeros([nx, ny])

        alphamap[MaskIndices[:, 0], MaskIndices[:, 1]] = alpha
        Irefmap[MaskIndices[:, 0], MaskIndices[:, 1]] = Iref
        alphastdmap[MaskIndices[:, 0], MaskIndices[:, 1]] = np.sqrt(varalpha)
        Irefstdmap[MaskIndices[:, 0], MaskIndices[:, 1]] = np.sqrt(varIref)

        if GiveComponents:
            return alphamap[None, None], alphastdmap[None, None], alpha
        else:
            return alphamap[None, None], alphastdmap[None, None]
コード例 #11
0
    def MakeMultiScaleCube(self):
        if self.CubePSFScales is not None: return
        print("Making MultiScale PSFs...", file=log)
        LScales = self.GD["HMP"]["Scales"]
        if 0 in LScales: LScales.remove(0)
        LRatios = self.GD["HMP"]["Ratios"]
        NTheta = self.GD["HMP"]["NTheta"]

        _, _, nx, ny = self.SubPSF.shape
        NScales = len(LScales)
        NRatios = len(LRatios)
        CubePSFScales = np.zeros(
            (NScales + 1 + NRatios * NTheta * (NScales), nx, ny))

        Scales = np.array(LScales)
        Ratios = np.array(LRatios)

        self.ListScales = []
        CubePSFScales[0, :, :] = self.SubPSF[0, 0, :, :]
        self.ListScales.append({"ModelType": "Delta"})
        iSlice = 1

        Support = 61

        for i in range(NScales):
            Minor = Scales[i] / (2. * np.sqrt(2. * np.log(2.)))
            Major = Minor
            PSFGaussPars = (Major, Minor, 0.)
            CubePSFScales[iSlice, :, :] = ModFFTW.ConvolveGaussian(
                self.SubPSF, CellSizeRad=1., GaussPars=[PSFGaussPars])[0, 0]
            Gauss = ModFFTW.GiveGauss(Support,
                                      CellSizeRad=1.,
                                      GaussPars=PSFGaussPars)
            self.ListScales.append({
                "ModelType": "Gaussian",
                "Model": Gauss,
                "ModelParams": PSFGaussPars,
                "Scale": i
            })

            iSlice += 1

        Theta = np.arange(0., np.pi - 1e-3, np.pi / NTheta)

        for iScale in range(NScales):
            for ratio in Ratios:
                for th in Theta:
                    Minor = Scales[iScale] / (2. * np.sqrt(2. * np.log(2.)))
                    Major = Minor * ratio
                    PSFGaussPars = (Major, Minor, th)
                    CubePSFScales[iSlice, :, :] = ModFFTW.ConvolveGaussian(
                        self.SubPSF, CellSizeRad=1.,
                        GaussPars=[PSFGaussPars])[0, 0]
                    Max = np.max(CubePSFScales[iSlice, :, :])
                    CubePSFScales[iSlice, :, :] /= Max
                    # pylab.clf()
                    # pylab.subplot(1,2,1)
                    # pylab.imshow(CubePSFScales[0,:,:],interpolation="nearest")
                    # pylab.subplot(1,2,2)
                    # pylab.imshow(CubePSFScales[iSlice,:,:],interpolation="nearest")
                    # pylab.title("Scale = %s"%str(PSFGaussPars))
                    # pylab.draw()
                    # pylab.show(False)
                    # pylab.pause(0.1)
                    iSlice += 1
                    Gauss = ModFFTW.GiveGauss(
                        Support, CellSizeRad=1., GaussPars=PSFGaussPars) / Max
                    self.ListScales.append({
                        "ModelType": "Gaussian",
                        "Model": Gauss,
                        "ModelParams": PSFGaussPars,
                        "Scale": iScale
                    })

        # Max=np.max(np.max(CubePSFScales,axis=1),axis=1)
        # Max=Max.reshape((Max.size,1,1))
        # CubePSFScales=CubePSFScales/Max

        self.CubePSFScales = np.float32(CubePSFScales)
        self.WeightWidth = 6
        CellSizeRad = 1.
        PSFGaussPars = (self.WeightWidth, self.WeightWidth, 0.)
        self.WeightFunction = ModFFTW.GiveGauss(self.SubPSF.shape[-1],
                                                CellSizeRad=1.,
                                                GaussPars=PSFGaussPars)
        #self.WeightFunction.fill(1)
        self.SupWeightWidth = 3. * self.WeightWidth
        print("   ... Done", file=log)
コード例 #12
0
    def giveBrutalRestored(self, DicoResidual):
        print >> log, "  Running Brutal deconvolution..."
        ListSilentModules = [
            "ClassImageDeconvMachineMSMF", "ClassPSFServer",
            "ClassMultiScaleMachine", "GiveModelMachine",
            "ClassModelMachineMSMF", "ClassImageDeconvMachineHogbom",
            "ClassModelMachineHogbom"
        ]
        # MyLogger.setSilent(ListSilentModules)
        self.DicoDirty = DicoResidual
        self.Orig_MeanDirty = self.DicoDirty["MeanImage"].copy()
        self.Orig_Dirty = self.DicoDirty["ImageCube"].copy()

        if self.NoiseMapReShape is not None:
            print >> log, "Deconvolving on SNR map"
            self.DeconvMachine.RMSFactor = 0

        self.DeconvMachine.Init(
            PSFVar=self.DicoVariablePSF,
            PSFAve=self.DicoVariablePSF["EstimatesAvgPSF"][-1],
            GridFreqs=self.GridFreqs,
            DegridFreqs=self.DegridFreqs,
            RefFreq=self.RefFreq)

        if self.NoiseMapReShape is not None:
            self.DeconvMachine.setNoiseMap(self.NoiseMapReShape,
                                           PNRStop=self.GD["Mask"]["SigTh"])

        # # #########################
        # # debug
        # MaskImage=image("image_dirin_SSD_test.dirty.fits.mask.fits").getdata()
        # nch,npol,_,_=MaskImage.shape
        # MaskArray=np.zeros(MaskImage.shape,np.bool8)
        # for ch in range(nch):
        #     for pol in range(npol):
        #         MaskArray[ch,pol,:,:]=np.bool8(MaskImage[ch,pol].T[::-1].copy())[:,:]
        # self.DeconvMachine.setMask(np.bool8(1-MaskArray))
        # # #########################

        self.DeconvMachine.Update(self.DicoDirty, DoSetMask=False)
        self.DeconvMachine.updateRMS()

        # ModConstructor = ClassModModelMachine(self.GD)
        # ModelMachine = ModConstructor.GiveMM(Mode=self.GD["Deconv"]["Mode"])
        # #print "ModelMachine"
        # #time.sleep(30)
        # self.ModelMachine=ModelMachine
        # #self.ModelMachine.DicoSMStacked=self.DicoBasicModelMachine
        # self.ModelMachine.setRefFreq(self.RefFreq,Force=True)
        # self.MinorCycleConfig["ModelMachine"] = ModelMachine
        # #self.ModelMachine.setModelShape(self.SubDirty.shape)
        # #self.ModelMachine.setListComponants(self.DeconvMachine.ModelMachine.ListScales)
        # #self.DeconvMachine.Update(self.DicoSubDirty,DoSetMask=False)
        # #self.DeconvMachine.updateMask(np.logical_not(self.SubMask))
        # self.DeconvMachine.updateModelMachine(ModelMachine)
        self.DeconvMachine.resetCounter()
        self.DeconvMachine.Deconvolve(UpdateRMS=False)

        print >> log, "  Getting model image..."
        Model = self.ModelMachine.GiveModelImage(DoAbs=True)
        if "Comp" in self.ExternalModelMachine.DicoSMStacked.keys():
            Model += np.abs(self.ExternalModelMachine.GiveModelImage())
        ModelImage = Model[0, 0]

        print >> log, "  Convolving image with beam %s..." % str(
            self.DicoVariablePSF["EstimatesAvgPSF"][1])
        #from DDFacet.ToolsDir import Gaussian

        # Sig_rad=np.max(self.DicoVariablePSF["EstimatesAvgPSF"][1][0:2])
        # Sig_pix=Sig_rad/self.DicoDirty["ImageInfo"]["CellSizeRad"]
        # Sig_pix=np.max([1,Sig_pix])#*2
        # n_pix=int(Sig_pix*4)
        # if n_pix%2==0: n_pix+=1

        # _,_,G=Gaussian.GaussianSymetric(Sig_pix,n_pix)

        # from DDFacet.ToolsDir.GiveEdges import GiveEdgesDissymetric

        # N1=G.shape[0]
        # N0x,N0y=ModelImage.shape
        # indx,indy=np.where(ModelImage!=0)
        # ModelConv=np.zeros_like(ModelImage)
        # for iComp in range(indx.size):
        #     xc,yc=indx[iComp],indy[iComp]
        #     Aedge,Bedge=GiveEdgesDissymetric((xc,yc),(N0x,N0y),(N1/2,N1/2),(N1,N1))
        #     x0d,x1d,y0d,y1d=Aedge
        #     x0p,x1p,y0p,y1p=Bedge
        #     ModelConv[x0d:x1d,y0d:y1d]+=G[x0p:x1p,y0p:y1p]*ModelImage[xc,yc]

        # # ModelConv=scipy.signal.convolve2d(ModelImage,G,mode="same")

        ModelConv = ModFFTW.ConvolveGaussian(
            {0: Model},
            0,
            0,
            0,
            CellSizeRad=self.DicoDirty["ImageInfo"]["CellSizeRad"],
            GaussPars_ch=self.DicoVariablePSF["EstimatesAvgPSF"][1])

        #GaussPar=[i*5 for i in self.DicoVariablePSF["EstimatesAvgPSF"][1]]
        #ModelConv+=ModFFTW.ConvolveGaussian(Model, CellSizeRad=self.DicoDirty["ImageInfo"]["CellSizeRad"],
        #                                    GaussPars=[GaussPar])

        self.ModelConv = ModelConv.reshape(self.DicoDirty["MeanImage"].shape)

        self.Restored = self.ModelConv + self.DicoDirty["MeanImage"]

        self.DicoDirty["MeanImage"][...] = self.Orig_MeanDirty[...]
        self.DicoDirty["ImageCube"][...] = self.Orig_Dirty[...]

        self.DeconvMachine.Reset()
        #MyLogger.setLoud(ListSilentModules)
        return self.Restored
コード例 #13
0
    def GiveSpectralIndexMap(self,
                             GaussPars=[(1, 1, 0)],
                             ResidCube=None,
                             GiveComponents=False,
                             ChannelWeights=None):

        # convert to radians
        ex, ey, pa = GaussPars
        ex *= np.pi / 180
        ey *= np.pi / 180
        pa *= np.pi / 180

        # get in terms of number of cells
        CellSizeRad = self.GD['Image']['Cell'] * np.pi / 648000
        # ex /= self.GD['Image']['Cell'] * np.pi / 648000
        # ey /= self.GD['Image']['Cell'] * np.pi / 648000

        # get Gaussian kernel
        GaussKern = ModFFTW.GiveGauss(self.Npix,
                                      CellSizeRad=CellSizeRad,
                                      GaussPars=(ex, ey, pa),
                                      parallel=False)

        # take FT
        Fs = np.fft.fftshift
        iFs = np.fft.ifftshift
        npad = self.Npad
        FTarray = self.ScaleMachine.FTMachine.xhatim.view()
        FTarray[...] = iFs(np.pad(GaussKern[None, None],
                                  ((0, 0), (0, 0), (npad, npad), (npad, npad)),
                                  mode='constant'),
                           axes=(2, 3))

        # this puts the FT in FTarray
        self.ScaleMachine.FTMachine.FFTim()

        # need to copy since FTarray and FTcube are views to the same array
        FTkernel = FTarray.copy()

        # evaluate model
        ModelImage = self.GiveModelImage(self.GridFreqs)

        # pad and take FT
        FTcube = self.ScaleMachine.FTMachine.Chatim.view()
        FTcube[...] = iFs(np.pad(ModelImage,
                                 ((0, 0), (0, 0), (npad, npad), (npad, npad)),
                                 mode='constant'),
                          axes=(2, 3))
        self.ScaleMachine.FTMachine.CFFTim()

        # multiply by kernel
        FTcube *= FTkernel

        # take iFT
        self.ScaleMachine.FTMachine.iCFFTim()

        I = slice(npad, -npad)

        ConvModelImage = Fs(FTcube, axes=(2, 3))[:, :, I, I].real

        ConvModelMean = np.mean(ConvModelImage.squeeze(), axis=0)

        ConvModelLow = ConvModelImage[-1, 0]
        ConvModelHigh = ConvModelImage[0, 0]

        if ResidCube is not None:
            ConvModelImage += ResidCube

        ConvModelImage = ConvModelImage.squeeze()

        RMS = np.std(ResidCube.flatten())

        Threshold = self.GD["SPIMaps"]["AlphaThreshold"] * RMS

        # get minimum along any freq axis
        MinImage = np.amin(ConvModelImage, axis=0)
        MaskIndices = np.argwhere(MinImage > Threshold)
        FitCube = ConvModelImage[:, MaskIndices[:, 0], MaskIndices[:, 1]]

        # Initial guess for I0
        I0i = ConvModelMean[MaskIndices[:, 0], MaskIndices[:, 1]]

        # initial guess for alphas
        Ilow = ConvModelLow[MaskIndices[:, 0], MaskIndices[:, 1]] / I0i
        Ihigh = ConvModelHigh[MaskIndices[:, 0], MaskIndices[:, 1]] / I0i
        alphai = (np.log(Ihigh) -
                  np.log(Ilow)) / (np.log(self.GridFreqs[0] / self.RefFreq) -
                                   np.log(self.GridFreqs[-1] / self.RefFreq))

        # import matplotlib.pyplot as plt
        #
        # for i in xrange(self.Nchan):
        #     plt.imshow(np.where(ConvModelImage[i] > Threshold, ConvModelImage[i], 0.0))
        #     plt.show()

        if ChannelWeights is None:
            weights = np.ones(self.Nchan, dtype=np.float32)
        else:
            weights = ChannelWeights.astype(np.float32)
            if ChannelWeights.size != self.Nchan:
                import warnings
                warnings.warn(
                    "The provided channel weights are of incorrect length. Ignoring weights.",
                    RuntimeWarning)
                weights = np.ones(self.Nchan, dtype=np.float32)

        try:
            import traceback
            from africanus.model.spi.dask import fit_spi_components
            NCPU = self.GD["Parallel"]["NCPU"]
            if NCPU:
                from multiprocessing.pool import ThreadPool
                import dask

                dask.config.set(pool=ThreadPool(NCPU))
            else:
                import multiprocessing
                NCPU = multiprocessing.cpu_count()

            import dask.array as da
            _, ncomps = FitCube.shape
            FitCubeDask = da.from_array(FitCube.T.astype(np.float64),
                                        chunks=(ncomps // NCPU, self.Nchan))
            weightsDask = da.from_array(weights.astype(np.float64),
                                        chunks=(self.Nchan))
            freqsDask = da.from_array(self.GridFreqs.astype(np.float64),
                                      chunks=(self.Nchan))

            alpha, varalpha, Iref, varIref = fit_spi_components(
                FitCubeDask,
                weightsDask,
                freqsDask,
                self.RefFreq,
                dtype=np.float64,
                I0i=I0i,
                alphai=alphai).compute()

            # from africanus.model.spi import fit_spi_components
            #
            # alpha, varalpha, Iref, varIref = fit_spi_components(FitCube.T.astype(np.float64), weights.astype(np.float64),
            #                                                     self.GridFreqs.astype(np.float64), self.RefFreq.astype(np.float64),
            #                                                     dtype=np.float64, I0i=I0i, alphai=alphai)
        except Exception as e:
            traceback_str = traceback.format_exc(e)
            print>>log, "Warning - Failed at importing africanus spi fitter. This could be an issue with the dask " \
                        "version. Falling back to (slow) scipy version"
            print >> log, "Original traceback - ", traceback_str
            alpha, varalpha, Iref, varIref = self.FreqMachine.FitSPIComponents(
                FitCube, self.GridFreqs, self.RefFreq)

        _, _, nx, ny = ModelImage.shape
        alphamap = np.zeros([nx, ny])
        Irefmap = np.zeros([nx, ny])
        alphastdmap = np.zeros([nx, ny])
        Irefstdmap = np.zeros([nx, ny])

        alphamap[MaskIndices[:, 0], MaskIndices[:, 1]] = alpha
        Irefmap[MaskIndices[:, 0], MaskIndices[:, 1]] = Iref
        alphastdmap[MaskIndices[:, 0], MaskIndices[:, 1]] = np.sqrt(varalpha)
        Irefstdmap[MaskIndices[:, 0], MaskIndices[:, 1]] = np.sqrt(varIref)

        if GiveComponents:
            return alphamap[None, None], alphastdmap[None, None], alpha
        else:
            return alphamap[None, None], alphastdmap[None, None]