Example #1
0
    def configure(self,
                  neurons,
                  lif=True,
                  saturation_range=(200, 300),
                  t_ref=0.001,
                  t_rc=0.01,
                  J_threshold=1,
                  activation_noise=0.1,
                  apply_noise=True,
                  threshold_coverage=0.9,
                  threshold_min=None,
                  threshold_max=None,
                  basis_style='Sphere',
                  sample_style='DefaultSampling',
                  sample_count=None,
                  seed=None,
                  code=None,
                  force_new=False,
                  use_hd=False,
                  basis=None,
                  thresholds=None,
                  saturations=None):
        self.neurons = neurons
        self.lif = lif
        self.saturation_range = saturation_range
        self.t_ref = t_ref
        self.t_rc = t_rc
        self.J_threshold = J_threshold
        self.basis_style = basis_style
        self.sample_style = sample_style
        self.threshold_coverage = threshold_coverage
        self.threshold_min = threshold_min
        self.threshold_max = threshold_max
        if sample_count is None: sample_count = self.dimensions * 500
        self.sample_count = sample_count
        self.activation_noise = activation_noise
        self.apply_noise = apply_noise
        self.decoders = {}
        self.use_hd = use_hd
        self.data_basis = basis
        self.data_thresholds = thresholds
        self.data_saturations = saturations

        self.storage = Storage(self, seed=seed, code=code, force_new=force_new)
        self.seed = self.storage.seed
        self.initialize_node()

        self.mode = 'rate'
Example #2
0
    def configure(self,neurons,lif=True,saturation_range=(200,300),
                  t_ref=0.001,t_rc=0.01,J_threshold=1,activation_noise=0.1,apply_noise=False,
                  threshold_coverage=0.9,threshold_min=None,threshold_max=None,
                  basis_style='Sphere',sample_style='DefaultSampling',
                  sample_count=None,seed=None,code=None,force_new=False,use_hd=False,
                  basis=None,thresholds=None,saturations=None,alphas=None,Jbiases=None):
        self.neurons=neurons
        self.lif=lif
        self.saturation_range=saturation_range
        self.t_ref=t_ref
        self.t_rc=t_rc
        self.J_threshold=J_threshold
        self.basis_style=basis_style
        self.sample_style=sample_style
        self.threshold_coverage=threshold_coverage
        self.threshold_min=threshold_min
        self.threshold_max=threshold_max
        if sample_count is None: 
            sample_count=self.dimensions*500
            if sample_count>5000: sample_count=5000
        self.sample_count=sample_count
        self.activation_noise=activation_noise
        self.apply_noise=apply_noise
        self.decoders={}
        self.use_hd=use_hd
        self.data_basis=basis
        self.data_thresholds=thresholds
        self.data_saturations=saturations
        self.data_alphas=alphas
        self.data_Jbiases=Jbiases

        self.storage=Storage(self,seed=seed,code=code,force_new=force_new)
        self.seed=self.storage.seed
        self.initialize_node()

        self.mode='rate'
        
        if self.sample_count<self.neurons:
            self.decoder_mode='NxS'
            self.decoder_noise_use_limit=True
        else:
            self.decoder_mode='NxN'
            self.decoder_noise_use_gamma=True  
class ActivityNode(ArrayNode):
    _set_activity=None
    decoder_size_warning=1000
    sample_step_size=500
    decoder_mode='NxN'
    decoder_noise_use_gamma=False
    decoder_noise_use_limit=False
    decoder_noise_use_activity=False
    
    
    lesion_size=0
    lesion_cells=None
    
    def configure(self,neurons,lif=True,saturation_range=(200,300),
                  t_ref=0.001,t_rc=0.01,J_threshold=1,activation_noise=0.1,apply_noise=False,
                  threshold_coverage=0.9,threshold_min=None,threshold_max=None,
                  basis_style='Sphere',sample_style='DefaultSampling',
                  sample_count=None,seed=None,code=None,force_new=False,use_hd=False,
                  basis=None,thresholds=None,saturations=None,alphas=None,Jbiases=None):
        self.neurons=neurons
        self.lif=lif
        self.saturation_range=saturation_range
        self.t_ref=t_ref
        self.t_rc=t_rc
        self.J_threshold=J_threshold
        self.basis_style=basis_style
        self.sample_style=sample_style
        self.threshold_coverage=threshold_coverage
        self.threshold_min=threshold_min
        self.threshold_max=threshold_max
        if sample_count is None: 
            sample_count=self.dimensions*500
            if sample_count>5000: sample_count=5000
        self.sample_count=sample_count
        self.activation_noise=activation_noise
        self.apply_noise=apply_noise
        self.decoders={}
        self.use_hd=use_hd
        self.data_basis=basis
        self.data_thresholds=thresholds
        self.data_saturations=saturations
        self.data_alphas=alphas
        self.data_Jbiases=Jbiases

        self.storage=Storage(self,seed=seed,code=code,force_new=force_new)
        self.seed=self.storage.seed
        self.initialize_node()

        self.mode='rate'
        
        if self.sample_count<self.neurons:
            self.decoder_mode='NxS'
            self.decoder_noise_use_limit=True
        else:
            self.decoder_mode='NxN'
            self.decoder_noise_use_gamma=True    


    def set(self,value,calc_output=True):
        ArrayNode.set(self,value,calc_output=False)
        if self.mode=='rate':
            if value is None:
                self._set_activity=None            
            else:
                c=self.array_to_current(self._set_array)+self.Jbias
                self._set_activity=self.current_to_activity(c)
        if calc_output: self._calc_output()


    def array(self):
        if self._array is None:
            if self.mode!='rate': return ArrayNode.array(self)
            self._array=self.activity_to_array(self._output)
        return self._array
        
    def _calc_output(self):
        if self.mode!='rate': return ArrayNode._calc_output(self)
        if self._set_activity is not None:
            out=self._set_activity
        else:
            out=self.current_to_activity(self.array_to_current(self.accumulator.value())+self.Jbias)
        if self.apply_noise:
            out=self.add_activation_noise(out)
        self._output=out
  
    def _transmit_rate_direct(self,conn,dt):
        x=self.activity_to_array(self._output,decoder=self.get_decoder(conn.func))
        conn.pop2.accumulator.add(conn.apply_weight(x),conn.tau,dt)
    def _transmit_rate_rate(self,conn,dt):
        x=self.activity_to_array(self._output,decoder=self.get_decoder(conn.func))
        conn.pop2.accumulator.add(conn.apply_weight(x),conn.tau,dt)
    def _transmit_direct_rate(self,conn,dt):
        conn.pop2.accumulator.add(conn.apply_func_weight(self._output),conn.tau,dt)


    def initialize_node(self):
        random=numpy.random.RandomState(seed=self.seed)
        
        if self.data_alphas is not None and self.data_Jbiases is not None:
            self.alpha=numpy.array([self.data_alphas[i%len(self.data_alphas)] for i in range(self.neurons)],dtype=numpy.dtype('float32'))
            self.Jbias=numpy.array([self.data_Jbiases[i%len(self.data_Jbiases)] for i in range(self.neurons)],dtype=numpy.dtype('float32'))
        else:
            if self.data_saturations is None:
                sr=self.saturation_range
                sat=random.uniform(sr[0],sr[1],(self.neurons,1))
            else:
                N=len(self.data_saturations)
                sat=numpy.array([[self.data_saturations[i%N] for i in range(self.neurons)]],dtype=numpy.dtype('float32')).T

            if self.data_thresholds is None:
                delta=(self.max-self.min)*(1-self.threshold_coverage)*0.5
                min_thresh=self.min+delta
                max_thresh=self.max-delta
                if self.threshold_min is not None: min_thresh=self.threshold_min
                if self.threshold_max is not None: max_thresh=self.threshold_max
                        
                thresh=random.uniform(min_thresh,max_thresh,(self.neurons,1))
            else:
                N=len(self.data_thresholds)
                thresh=numpy.array([[self.data_thresholds[i%N] for i in range(self.neurons)]],dtype=numpy.dtype('float32')).T
                
            self.initialize_neurons(sat,thresh)

        if self.data_basis is None:
            g=makeGenerator(self.basis_style,self.dimensions,int(random.randint(0x7FFFFFFF)))
            self.basis=g.get(self.neurons).T
        else:
            N=len(self.data_basis)
            self.basis=numpy.array([self.data_basis[i%N] for i in range(self.neurons)],dtype=numpy.dtype('float32'))
            if len(self.basis.shape)==1:
                self.basis.shape=(self.neurons,self.dimensions)

        self.sample_generator=makeGenerator(self.sample_style,self.dimensions,int(random.randint(0x7FFFFFFF)))
        if self.min!=-1 or self.max!=1:
            scale=(self.max-self.min)/2.0
            if scale!=1.0: self.sample_generator.scale=scale
            offset=(self.max+self.min)/2.0
            if scale!=0.0: self.sample_generator.offset=offset
        

    
        

    def initialize_neurons(self,saturations,thresholds):
        saturations=numpy.array(saturations,dtype=numpy.float32)
        thresholds=numpy.array(thresholds,dtype=numpy.float32)
        x1,y1=thresholds,numpy.zeros((self.neurons,1),dtype=numpy.float32)
        x2,y2=self.max,saturations
        if not self.lif:
            m=(y1-y2)/(x1-x2)
            b=y1-m*x1
        else:
            numpy.seterr(divide='ignore')
            z1=numpy.where(y1<=0,1.0,1.0/(1-numpy.exp((self.t_ref-(1.0/y1))/self.t_rc)))
            z2=numpy.where(y2<=0,1.0,1.0/(1-numpy.exp((self.t_ref-(1.0/y2))/self.t_rc)))
            numpy.seterr(divide='warn')
            m=(z1-z2)/(x1-x2)
            b=z1-m*x1            
        self.alpha,self.Jbias=m,b
        self.Jbias.shape=self.Jbias.shape[0]
        self.alpha.shape=self.alpha.shape[0]

    def current_to_activity(self,J):
        if not self.lif:
            return numpy.maximum(J,0)
        else:
            J=numpy.maximum(J,0)
            numpy.seterr(invalid='ignore',divide='ignore')
            G=self.t_ref-self.t_rc*numpy.log(1-self.J_threshold/J)
            G=numpy.where(G>0.001,1/G,0)
            numpy.seterr(invalid='warn',divide='warn')
            return G

        
    def array_to_current(self,array):
        b=self.basis
        phi_x=numpy.dot(b,array)
        J=self.alpha*phi_x
        return J

    def arrays_to_currents(self,arrays):
        b=self.basis
        phi_x=numpy.dot(b,arrays)
        J=self.alpha*phi_x.T
        return J.T

                
    def activity_to_array(self,activity,decoder=None):
        if activity is None: activity=numpy.zeros(self.neurons)
        if self.lesion_size>0: 
            activity=activity[:]
            activity[:self.lesion_size]=0.0
        if self.lesion_cells is not None:
            activity[self.lesion_cells]=0.0
        if decoder is None:
            decoder=self.get_decoder()
        array=numpy.dot(activity.T,decoder)            
        return array

    def add_activation_noise(self,actv,noise=None):
        if noise is None: noise=self.activation_noise
        if noise>0:
            actv=numpy.random.normal(actv,self.saturation_range[1]*noise)
            actv=numpy.maximum(0,actv)
        return actv

            
            
    def get_decoder(self,func=None,noise=None):
        if self.decoder_mode=='NxN':
            decoder=self.get_decoder_NxN
        elif self.decoder_mode=='NxS':
            decoder=self.get_decoder_NxS
        elif self.decoder_mode=='binary':
            decoder=self.get_decoder_binary
        else:
            raise Exception('Unknown decoder mode: %s'%self.decoder_mode)    
        return decoder(func=func,noise=noise)        
        
            

    def get_decoder_NxN(self,func=None,noise=None):
        if noise is None: noise=self.activation_noise

        name='decoderNxN'
        name_gamma='gamma'
        name_gammainv='gammainv'
        name_upsilon='upsilon'
        if func:
            hash_info=make_hash_info(func)
            n='-%s-%08x'%(func.__name__,hash(tuple(hash_info)))#hash(tuple(func_id)))
            n=n.replace('<','_').replace('>','_')
            name_upsilon+=n
            name+=n
        name+='-%4.2f'%noise
        name_gammainv+='-%4.2f'%noise
        if noise>0:
            if self.decoder_noise_use_gamma: 
                name+='g'
                name_gammainv+='g'
            if self.decoder_noise_use_limit: 
                name+='l'
                name_gammainv+='l'
            if self.decoder_noise_use_activity: 
                name+='a'
                name_gammainv+='a'
                name_upsilon+='-%4.2fa'%noise
                name_gamma+='-%4.2fa'%noise
            

        if name in self.decoders: return self.decoders[name]
        decoder=self.storage.get(name,(self.neurons,-1))
        if decoder is not None:
            self.decoders[name]=decoder
            return decoder


        warning=False
        if self.neurons>self.decoder_size_warning:
            warning=True
            print 'Warning: calculating decoder for size %d neural group.  This may take a while.'%self.neurons


        upsilon=None
        upsilon=self.storage.get(name_upsilon,(self.neurons,-1))

        need_gammainv=False
        need_gamma=False
        gamma_inv=self.storage.get(name_gammainv,(self.neurons,self.neurons))
        if gamma_inv is None:
            need_gammainv=True
            gamma=self.storage.get(name_gamma,(self.neurons,self.neurons))
            if gamma is None: need_gamma=True

        if need_gamma or upsilon is None:
          if self.dimensions>=3 and self.use_hd:
            gamma,moments=calc_gamma_moments(self,dr=0.01)
            gamma*=self.sample_count
            ups=self.basis*moments[1].reshape((moments[1].shape[0],1))*self.sample_count
            
          else:
        
            self.sample_generator.reset()
            count=self.sample_count
            ups=None
            while count>0:
                s=min(count,self.sample_step_size)
                if not self.sample_generator.can_continue(self.dimensions):
                    s=count
                if warning:
                    print 'processing %d of %d samples (%d left)'%(s,self.sample_count,count)
                samples=self.sample_generator.get(s)
                count-=s

                curr=self.arrays_to_currents(samples)
                curr=curr.T+self.Jbias
                actv=self.current_to_activity(curr.T)
                if self.decoder_noise_use_activity:
                    actv=numpy.random.normal(actv,noise*self.saturation_range[1])
                    actv=numpy.maximum(0,actv)
                    actv=numpy.array(actv,dtype=numpy.float32)

                if need_gamma:
                    g=numpy.dot(actv,actv.T)
                    if gamma is None: gamma=g
                    else: gamma+=g
                    
                if upsilon is None:
                    samples=samples.T
                    if func is not None:
                        if self.dimensions==1:
                            samples=samples[:,0]
                        samples=numpy.array([self.value_to_array(func(self.array_to_value(x))) for x in samples],dtype=numpy.float32)
                    u=numpy.dot(actv,samples)
                    if ups is None: ups=u
                    else: ups+=u
          if need_gamma:
                self.storage.set(name_gamma,gamma)                
          if upsilon is None:
                upsilon=ups
                self.storage.set(name_upsilon,upsilon)
                
        error_flag=False
        if need_gammainv:   
            if self.decoder_noise_use_gamma:
                if noise>0:
                    gamma+=numpy.identity(gamma.shape[0])*(((noise*self.saturation_range[1])**2)*self.sample_count)
        
            if warning:
                print 'inverting %dx%d gamma matrix'%gamma.shape
                    
            w,v=numpy.linalg.eigh(gamma)
            limit=svd_limit*max(w)
            
            if self.decoder_noise_use_limit:
                if noise>0: limit=noise*noise*max(w)
                
            for i in range(len(w)):
                if w[i]<limit: w[i]=0
                else: w[i]=1.0/w[i]
            gamma_inv=numpy.dot(v,numpy.multiply(w[:,numpy.core.newaxis],v.T))
            self.storage.set(name_gammainv,gamma_inv)                
        
        decoder=numpy.dot(gamma_inv,upsilon)
        if len(decoder.shape)==1:
            decoder.shape=decoder.shape[0],1

        self.decoders[name]=decoder
        self.storage.set(name,decoder)
        return decoder


    def get_decoder_NxS(self,func=None,noise=None):
        if noise is None: noise=self.activation_noise

        name='decoderNxS'
        name_Ainv='Ainv'
        name_B='B'
        if func:
            hash_info=make_hash_info(func)
            n='-%s-%08x'%(func.__name__,hash(tuple(hash_info)))#hash(tuple(func_id)))
            n=n.replace('<','_').replace('>','_')
            name_B+=n
            name+=n
        name+='-%4.2f'%noise
        name_Ainv+='-%4.2f'%noise
        if noise>0:
            if self.decoder_noise_use_limit: 
                name+='l'
                name_Ainv+'l'
            if self.decoder_noise_use_activity: 
                name+='a'
                name_Ainv+='a'
                name_B+='-%4.2fa'%noise



        
        
        if name in self.decoders: return self.decoders[name]
        decoder=self.storage.get(name,(self.neurons,-1))
        if decoder is not None:
            self.decoders[name]=decoder
            return decoder


        warning=False
        if self.neurons>self.decoder_size_warning:
            warning=True
            print 'Warning: calculating decoder for size %d neural group.  This may take a while.'%self.neurons


        B=self.storage.get(name_B,(self.sample_count,-1))
        Ainv=self.storage.get(name_Ainv,(self.sample_count,self.neurons))
        
        need_B=B is None
        need_A=Ainv is None
        
        if B is None or Ainv is None:
            self.sample_generator.reset()
            count=self.sample_count
            A=None
            while count>0:
                s=min(count,self.sample_step_size)
                if not self.sample_generator.can_continue(self.dimensions):
                    s=count
                if warning:
                    print 'processing %d of %d samples (%d left)'%(s,self.sample_count,count)
                samples=self.sample_generator.get(s)
                count-=s

                curr=self.arrays_to_currents(samples)
                curr=curr.T+self.Jbias
                actv=self.current_to_activity(curr.T)
                if self.decoder_noise_use_activity:
                    actv=numpy.random.normal(actv,noise*self.saturation_range[1])
                    actv=numpy.maximum(0,actv)
                    actv=numpy.array(actv,dtype=numpy.float32)
                
                if need_A:
                    if A is None: A=actv
                    else: 
                        A=numpy.hstack((A,actv))
                if need_B:
                    samples=samples.T
                    if func is not None:
                        if self.dimensions==1:
                            samples=samples[:,0]
                        samples=numpy.array([self.value_to_array(func(self.array_to_value(x))) for x in samples],dtype=numpy.float32)
                    if B is None: B=samples
                    else: 
                        B=numpy.vstack((B,samples))
        if need_A:
            if warning:
                print 'inverting %dx%d activity matrix'%A.shape
        
            Ainv=numpy.linalg.pinv(A,rcond=noise*0.1)
            self.storage.set(name_Ainv,Ainv)
        if need_B:
            self.storage.set(name_B,B)
            
            
        
        decoder=numpy.dot(Ainv.T,B)
        if len(decoder.shape)==1:
            decoder.shape=decoder.shape[0],1

        self.decoders[name]=decoder
        self.storage.set(name,decoder)
        return decoder
        
    def get_decoder_binary(self,func=None,noise=None):
        if noise is None: noise=self.activation_noise

        name='decoderBinary'
        name_A='A'
        name_B='B'
        if func:
            hash_info=make_hash_info(func)
            n='-%s-%08x'%(func.__name__,hash(tuple(hash_info)))#hash(tuple(func_id)))
            n=n.replace('<','_').replace('>','_')
            name_B+=n
            name+=n
        name+='-%4.2f'%noise
        name_A+='-%4.2f'%noise
        if noise>0:
            if self.decoder_noise_use_activity: 
                name+='a'
                name_A+='a'
                name_B+='-%4.2fa'%noise
        
        if name in self.decoders: return self.decoders[name]
        decoder=self.storage.get(name,(self.neurons,-1))
        if decoder is not None:
            self.decoders[name]=decoder
            return decoder

        warning=False
        if self.neurons>self.decoder_size_warning:
            warning=True
            print 'Warning: calculating decoder for size %d neural group.  This may take a while.'%self.neurons


        B=self.storage.get(name_B,(self.sample_count,-1))
        A=self.storage.get(name_A,(self.sample_count,self.neurons))
        
        need_B=B is None
        need_A=A is None
        
        if B is None or A is None:
            self.sample_generator.reset()
            count=self.sample_count
            A=None
            while count>0:
                s=min(count,self.sample_step_size)
                if not self.sample_generator.can_continue(self.dimensions):
                    s=count
                if warning:
                    print 'processing %d of %d samples (%d left)'%(s,self.sample_count,count)
                samples=self.sample_generator.get(s)
                count-=s

                curr=self.arrays_to_currents(samples)
                curr=curr.T+self.Jbias
                actv=self.current_to_activity(curr.T)
                if self.decoder_noise_use_activity:
                    actv=numpy.random.normal(actv,noise*self.saturation_range[1])
                    actv=numpy.maximum(0,actv)
                    actv=numpy.array(actv,dtype=numpy.float32)
                
                if need_A:
                    if A is None: A=actv
                    else: 
                        A=numpy.hstack((A,actv))
                if need_B:
                    samples=samples.T
                    if func is not None:
                        if self.dimensions==1:
                            samples=samples[:,0]
                        samples=numpy.array([self.value_to_array(func(self.array_to_value(x))) for x in samples],dtype=numpy.float32)
                    if B is None: B=samples
                    else: 
                        B=numpy.vstack((B,samples))
        if need_A:
            self.storage.set(name_A,A)
        if need_B:
            self.storage.set(name_B,B)
            

                    
        

        options=[0.0,1.0,-1.0]#,2.0,-2.0,3.0,-3.0]      
        import random

        dec=[]

        for index in range(B.shape[1]):
            d=None
            e=None
            B2=B[:,index]
            for a in range(10):
                decoder=numpy.array([random.choice(options) for i in range(len(A))])
                if len(decoder.shape)==1:
                    decoder.shape=decoder.shape[0],1

                scale=numpy.linalg.norm(B2)/numpy.linalg.norm(numpy.dot(A.T,decoder))
                decoder*=scale

                
                error=numpy.linalg.norm(numpy.dot(A.T,decoder)-B2)
                for i in range(500):
                    #print i,error
                    j=random.randrange(len(actv))
                    val=random.choice(options)*scale
                    if val!=decoder[j][0]:
                        oldval=decoder[j][0]
                        decoder[j][0]=val
                        error2=numpy.linalg.norm(numpy.dot(A.T,decoder)-B2)
                        if error2>=error:
                            decoder[j][0]=oldval
                        else:
                            error=error2
                            scale2=numpy.linalg.norm(B2)/numpy.linalg.norm(numpy.dot(A.T,decoder))
                            scale*=scale2
                            decoder*=scale2
                if e is None or error<e:
                    d=decoder
                    e=error
            dec.append(d)

        decoder=numpy.array(dec).T
        decoder.shape=self.basis.shape
        #import scipy.io as sio
        #sio.savemat('example%08x.mat'%self.seed,dict(A=A,B=B,dec=decoder))

        self.decoders[name]=decoder
        self.storage.set(name,decoder)
        return decoder
Example #4
0
class ActivityNode(ArrayNode):
    _set_activity=None
    decoder_size_warning=1000
    sample_step_size=500
    decoder_mode='NxN'
    decoder_noise_use_gamma=False
    decoder_noise_use_limit=False
    decoder_noise_use_activity=False
    
    
    lesion_size=0
    lesion_cells=None
    
    def configure(self,neurons,lif=True,saturation_range=(200,300),
                  t_ref=0.001,t_rc=0.01,J_threshold=1,activation_noise=0.1,apply_noise=False,
                  threshold_coverage=0.9,threshold_min=None,threshold_max=None,
                  basis_style='Sphere',sample_style='DefaultSampling',
                  sample_count=None,seed=None,code=None,force_new=False,use_hd=False,
                  basis=None,thresholds=None,saturations=None,alphas=None,Jbiases=None):
        self.neurons=neurons
        self.lif=lif
        self.saturation_range=saturation_range
        self.t_ref=t_ref
        self.t_rc=t_rc
        self.J_threshold=J_threshold
        self.basis_style=basis_style
        self.sample_style=sample_style
        self.threshold_coverage=threshold_coverage
        self.threshold_min=threshold_min
        self.threshold_max=threshold_max
        if sample_count is None: 
            sample_count=self.dimensions*500
            if sample_count>5000: sample_count=5000
        self.sample_count=sample_count
        self.activation_noise=activation_noise
        self.apply_noise=apply_noise
        self.decoders={}
        self.use_hd=use_hd
        self.data_basis=basis
        self.data_thresholds=thresholds
        self.data_saturations=saturations
        self.data_alphas=alphas
        self.data_Jbiases=Jbiases

        self.storage=Storage(self,seed=seed,code=code,force_new=force_new)
        self.seed=self.storage.seed
        self.initialize_node()

        self.mode='rate'
        
        if self.sample_count<self.neurons:
            self.decoder_mode='NxS'
            self.decoder_noise_use_limit=True
        else:
            self.decoder_mode='NxN'
            self.decoder_noise_use_gamma=True  
            


    def set(self,value,calc_output=True):
        ArrayNode.set(self,value,calc_output=False)
        if self.mode=='rate':
            if value is None:
                self._set_activity=None            
            else:
                c=self.array_to_current(self._set_array)+self.Jbias
                self._set_activity=self.current_to_activity(c)
        if calc_output: self._calc_output()


    def array(self):
        if self._array is None:
            if self.mode!='rate': return ArrayNode.array(self)
            self._array=self.activity_to_array(self._output)
        return self._array
        
    def _calc_output(self):
        if self.mode!='rate': return ArrayNode._calc_output(self)
        if self._set_activity is not None:
            out=self._set_activity
        else:
            out=self.current_to_activity(self.array_to_current(self.accumulator.value())+self.Jbias)
        if self.apply_noise:
            out=self.add_activation_noise(out)
        self._output=out
  
    def _transmit_rate_direct(self,conn,dt):
        x=self.activity_to_array(self._output,decoder=self.get_decoder(conn.func))
        conn.pop2.accumulator.add(conn.apply_weight(x),conn.tau,dt)
    def _transmit_rate_rate(self,conn,dt):
        x=self.activity_to_array(self._output,decoder=self.get_decoder(conn.func))
        conn.pop2.accumulator.add(conn.apply_weight(x),conn.tau,dt)
    def _transmit_direct_rate(self,conn,dt):
        conn.pop2.accumulator.add(conn.apply_func_weight(self._output),conn.tau,dt)


    def initialize_node(self):
        random=numpy.random.RandomState(seed=self.seed)
        
        if self.data_alphas is not None and self.data_Jbiases is not None:
            self.alpha=numpy.array([self.data_alphas[i%len(self.data_alphas)] for i in range(self.neurons)],dtype=numpy.dtype('float32'))
            self.Jbias=numpy.array([self.data_Jbiases[i%len(self.data_Jbiases)] for i in range(self.neurons)],dtype=numpy.dtype('float32'))
        else:
            if self.data_saturations is None:
                sr=self.saturation_range
                sat=random.uniform(sr[0],sr[1],(self.neurons,1))
            else:
                N=len(self.data_saturations)
                sat=numpy.array([[self.data_saturations[i%N] for i in range(self.neurons)]],dtype=numpy.dtype('float32')).T

            if self.data_thresholds is None:
                delta=(self.max-self.min)*(1-self.threshold_coverage)*0.5
                min_thresh=self.min+delta
                max_thresh=self.max-delta
                if self.threshold_min is not None: min_thresh=self.threshold_min
                if self.threshold_max is not None: max_thresh=self.threshold_max
                        
                thresh=random.uniform(min_thresh,max_thresh,(self.neurons,1))
            else:
                N=len(self.data_thresholds)
                thresh=numpy.array([[self.data_thresholds[i%N] for i in range(self.neurons)]],dtype=numpy.dtype('float32')).T
                
            self.initialize_neurons(sat,thresh)

        if self.data_basis is None:
            g=makeGenerator(self.basis_style,self.dimensions,int(random.randint(0x7FFFFFFF)))
            self.basis=g.get(self.neurons).T
        else:
            N=len(self.data_basis)
            self.basis=numpy.array([self.data_basis[i%N] for i in range(self.neurons)],dtype=numpy.dtype('float32'))
            if len(self.basis.shape)==1:
                self.basis.shape=(self.neurons,self.dimensions)

        self.sample_generator=makeGenerator(self.sample_style,self.dimensions,int(random.randint(0x7FFFFFFF)))
        if self.min!=-1 or self.max!=1:
            scale=(self.max-self.min)/2.0
            if scale!=1.0: self.sample_generator.scale=scale
            offset=(self.max+self.min)/2.0
            if scale!=0.0: self.sample_generator.offset=offset
        

    
        

    def initialize_neurons(self,saturations,thresholds):
        saturations=numpy.array(saturations,dtype=numpy.float32)
        thresholds=numpy.array(thresholds,dtype=numpy.float32)
        x1,y1=thresholds,numpy.zeros((self.neurons,1),dtype=numpy.float32)
        x2,y2=self.max,saturations
        if not self.lif:
            m=(y1-y2)/(x1-x2)
            b=y1-m*x1
        else:
            numpy.seterr(divide='ignore')
            z1=numpy.where(y1<=0,1.0,1.0/(1-numpy.exp((self.t_ref-(1.0/y1))/self.t_rc)))
            z2=numpy.where(y2<=0,1.0,1.0/(1-numpy.exp((self.t_ref-(1.0/y2))/self.t_rc)))
            numpy.seterr(divide='warn')
            m=(z1-z2)/(x1-x2)
            b=z1-m*x1            
        self.alpha,self.Jbias=m,b
        self.Jbias.shape=self.Jbias.shape[0]
        self.alpha.shape=self.alpha.shape[0]

    def current_to_activity(self,J):
        if not self.lif:
            return numpy.maximum(J,0)
        else:
            J=numpy.maximum(J,0)
            numpy.seterr(invalid='ignore',divide='ignore')
            G=self.t_ref-self.t_rc*numpy.log(1-self.J_threshold/J)
            G=numpy.where(G>0.001,1/G,0)
            numpy.seterr(invalid='warn',divide='warn')
            return G

        
    def array_to_current(self,array):
        b=self.basis
        phi_x=numpy.dot(b,array)
        J=self.alpha*phi_x
        return J

    def arrays_to_currents(self,arrays):
        b=self.basis
        phi_x=numpy.dot(b,arrays)
        J=self.alpha*phi_x.T
        return J.T

                
    def activity_to_array(self,activity,decoder=None):
        if activity is None: activity=numpy.zeros(self.neurons)
        if self.lesion_size>0: 
            activity=activity[:]
            activity[:self.lesion_size]=0.0
        if self.lesion_cells is not None:
            activity[self.lesion_cells]=0.0
        if decoder is None:
            decoder=self.get_decoder()
        array=numpy.dot(activity.T,decoder)            
        return array

    def add_activation_noise(self,actv,noise=None):
        if noise is None: noise=self.activation_noise
        if noise>0:
            actv=numpy.random.normal(actv,self.saturation_range[1]*noise)
            actv=numpy.maximum(0,actv)
        return actv

            
            
    def get_decoder(self,func=None,noise=None):
        if self.decoder_mode=='NxN':
            decoder=self.get_decoder_NxN
        elif self.decoder_mode=='NxS':
            decoder=self.get_decoder_NxS
        else:
            raise Exception('Unknown decoder mode: %s'%self.decoder_mode)    
        return decoder(func=func,noise=noise)        
        
            

    def get_decoder_NxN(self,func=None,noise=None):
        if noise is None: noise=self.activation_noise

        name='decoderNxN'
        name_gamma='gamma'
        name_gammainv='gammainv'
        name_upsilon='upsilon'
        if func:
            hash_info=make_hash_info(func)
            n='-%s-%08x'%(func.__name__,hash(tuple(hash_info)))#hash(tuple(func_id)))
            n=n.replace('<','_').replace('>','_')
            name_upsilon+=n
            name+=n
        name+='-%4.2f'%noise
        name_gammainv+='-%4.2f'%noise
        if noise>0:
            if self.decoder_noise_use_gamma: 
                name+='g'
                name_gammainv+='g'
            if self.decoder_noise_use_limit: 
                name+='l'
                name_gammainv+='l'
            if self.decoder_noise_use_activity: 
                name+='a'
                name_gammainv+='a'
                name_upsilon+='-%4.2fa'%noise
                name_gamma+='-%4.2fa'%noise
            

        if name in self.decoders: return self.decoders[name]
        decoder=self.storage.get(name,(self.neurons,-1))
        if decoder is not None:
            self.decoders[name]=decoder
            return decoder


        warning=False
        if self.neurons>self.decoder_size_warning:
            warning=True
            print('Warning: calculating decoder for size %d neural group.  This may take a while.'%self.neurons)


        upsilon=None
        upsilon=self.storage.get(name_upsilon,(self.neurons,-1))

        need_gammainv=False
        need_gamma=False
        gamma_inv=self.storage.get(name_gammainv,(self.neurons,self.neurons))
        if gamma_inv is None:
            need_gammainv=True
            gamma=self.storage.get(name_gamma,(self.neurons,self.neurons))
            if gamma is None: need_gamma=True

        if need_gamma or upsilon is None:
          if self.dimensions>=3 and self.use_hd:
            gamma,moments=calc_gamma_moments(self,dr=0.01)
            gamma*=self.sample_count
            ups=self.basis*moments[1].reshape((moments[1].shape[0],1))*self.sample_count
            
          else:
        
            self.sample_generator.reset()
            count=self.sample_count
            ups=None
            while count>0:
                s=min(count,self.sample_step_size)
                if not self.sample_generator.can_continue(self.dimensions):
                    s=count
                if warning:
                    print('processing %d of %d samples (%d left)'%(s,self.sample_count,count))
                samples=self.sample_generator.get(s)
                count-=s

                curr=self.arrays_to_currents(samples)
                curr=curr.T+self.Jbias
                actv=self.current_to_activity(curr.T)
                if self.decoder_noise_use_activity:
                    actv=numpy.random.normal(actv,noise*self.saturation_range[1])
                    actv=numpy.maximum(0,actv)
                    actv=numpy.array(actv,dtype=numpy.float32)

                if need_gamma:
                    g=numpy.dot(actv,actv.T)
                    if gamma is None: gamma=g
                    else: gamma+=g
                    
                if upsilon is None:
                    samples=samples.T
                    if func is not None:
                        if self.dimensions==1:
                            samples=samples[:,0]
                        samples=numpy.array([self.value_to_array(func(self.array_to_value(x))) for x in samples],dtype=numpy.float32)
                    u=numpy.dot(actv,samples)
                    if ups is None: ups=u
                    else: ups+=u
          if need_gamma:
                self.storage.set(name_gamma,gamma)                
          if upsilon is None:
                upsilon=ups
                self.storage.set(name_upsilon,upsilon)
                
        error_flag=False
        if need_gammainv:   
            if self.decoder_noise_use_gamma:
                if noise>0:
                    gamma+=numpy.identity(gamma.shape[0])*(((noise*self.saturation_range[1])**2)*self.sample_count)
        
            if warning:
                print('inverting %dx%d gamma matrix'%gamma.shape)
                    
            w,v=numpy.linalg.eigh(gamma)
            limit=svd_limit*max(w)
            
            if self.decoder_noise_use_limit:
                if noise>0: limit=noise*noise*max(w)
                
            for i in range(len(w)):
                if w[i]<limit: w[i]=0
                else: w[i]=1.0/w[i]
            gamma_inv=numpy.dot(v,numpy.multiply(w[:,numpy.core.newaxis],v.T))
            self.storage.set(name_gammainv,gamma_inv)                
        
        decoder=numpy.dot(gamma_inv,upsilon)
        if len(decoder.shape)==1:
            decoder.shape=decoder.shape[0],1

        self.decoders[name]=decoder
        self.storage.set(name,decoder)
        return decoder


    def get_decoder_NxS(self,func=None,noise=None):
        if noise is None: noise=self.activation_noise

        name='decoderNxS'
        name_Ainv='Ainv'
        name_B='B'
        if func:
            hash_info=make_hash_info(func)
            n='-%s-%08x'%(func.__name__,hash(tuple(hash_info)))#hash(tuple(func_id)))
            n=n.replace('<','_').replace('>','_')
            name_B+=n
            name+=n
        name+='-%4.2f'%noise
        name_Ainv+='-%4.2f'%noise
        if noise>0:
            if self.decoder_noise_use_limit: 
                name+='l'
                name_Ainv+'l'
            if self.decoder_noise_use_activity: 
                name+='a'
                name_Ainv+='a'
                name_B+='-%4.2fa'%noise



        
        
        if name in self.decoders: return self.decoders[name]
        decoder=self.storage.get(name,(self.neurons,-1))
        if decoder is not None:
            self.decoders[name]=decoder
            return decoder


        warning=False
        if self.neurons>self.decoder_size_warning:
            warning=True
            print('Warning: calculating decoder for size %d neural group.  This may take a while.'%self.neurons)


        B=self.storage.get(name_B,(self.sample_count,-1))
        Ainv=self.storage.get(name_Ainv,(self.sample_count,self.neurons))
        
        need_B=B is None
        need_A=Ainv is None
        
        if B is None or Ainv is None:
            self.sample_generator.reset()
            count=self.sample_count
            A=None
            while count>0:
                s=min(count,self.sample_step_size)
                if not self.sample_generator.can_continue(self.dimensions):
                    s=count
                if warning:
                    print('processing %d of %d samples (%d left)'%(s,self.sample_count,count))
                samples=self.sample_generator.get(s)
                count-=s

                curr=self.arrays_to_currents(samples)
                curr=curr.T+self.Jbias
                actv=self.current_to_activity(curr.T)
                if self.decoder_noise_use_activity:
                    actv=numpy.random.normal(actv,noise*self.saturation_range[1])
                    actv=numpy.maximum(0,actv)
                    actv=numpy.array(actv,dtype=numpy.float32)
                
                if need_A:
                    if A is None: A=actv
                    else: 
                        A=numpy.hstack((A,actv))
                if need_B:
                    samples=samples.T
                    if func is not None:
                        if self.dimensions==1:
                            samples=samples[:,0]
                        samples=numpy.array([self.value_to_array(func(self.array_to_value(x))) for x in samples],dtype=numpy.float32)
                    if B is None: B=samples
                    else: 
                        B=numpy.vstack((B,samples))
        if need_A:
            if warning:
                print('inverting %dx%d activity matrix'%A.shape)
        
            Ainv=numpy.linalg.pinv(A,rcond=noise*0.1)
            self.storage.set(name_Ainv,Ainv)
        if need_B:
            self.storage.set(name_B,B)
            
            
        
        decoder=numpy.dot(Ainv.T,B)
        if len(decoder.shape)==1:
            decoder.shape=decoder.shape[0],1

        self.decoders[name]=decoder
        self.storage.set(name,decoder)
        return decoder
Example #5
0
class ActivityNode(ArrayNode):
    _set_activity = None
    decoder_size_warning = 1000
    decoder_size_limit = 5000
    sample_step_size = 500

    def configure(self,
                  neurons,
                  lif=True,
                  saturation_range=(200, 300),
                  t_ref=0.001,
                  t_rc=0.01,
                  J_threshold=1,
                  activation_noise=0.1,
                  apply_noise=True,
                  threshold_coverage=0.9,
                  threshold_min=None,
                  threshold_max=None,
                  basis_style='Sphere',
                  sample_style='DefaultSampling',
                  sample_count=None,
                  seed=None,
                  code=None,
                  force_new=False,
                  use_hd=False,
                  basis=None,
                  thresholds=None,
                  saturations=None):
        self.neurons = neurons
        self.lif = lif
        self.saturation_range = saturation_range
        self.t_ref = t_ref
        self.t_rc = t_rc
        self.J_threshold = J_threshold
        self.basis_style = basis_style
        self.sample_style = sample_style
        self.threshold_coverage = threshold_coverage
        self.threshold_min = threshold_min
        self.threshold_max = threshold_max
        if sample_count is None: sample_count = self.dimensions * 500
        self.sample_count = sample_count
        self.activation_noise = activation_noise
        self.apply_noise = apply_noise
        self.decoders = {}
        self.use_hd = use_hd
        self.data_basis = basis
        self.data_thresholds = thresholds
        self.data_saturations = saturations

        self.storage = Storage(self, seed=seed, code=code, force_new=force_new)
        self.seed = self.storage.seed
        self.initialize_node()

        self.mode = 'rate'

    def set(self, value, calc_output=True):
        ArrayNode.set(self, value, calc_output=False)
        if self.mode == 'rate':
            c = self.array_to_current(self._set_array) + self.Jbias
            self._set_activity = self.current_to_activity(c)
        if calc_output: self._calc_output()

    def array(self):
        if self._array is None:
            if self.mode != 'rate': return ArrayNode.array(self)
            self._array = self.activity_to_array(self._output)
        return self._array

    def _calc_output(self):
        if self.mode != 'rate': return ArrayNode._calc_output(self)
        if self._set_activity is not None:
            out = self._set_activity
        elif self._input is not None:
            out = self.current_to_activity(self._input)
        else:
            out = numpy.zeros(self.neurons)
        if self.apply_noise:
            out = self.add_activation_noise(out)
        self._output = out

    def _clear_inputs(self):
        if self.mode != 'rate': return ArrayNode._clear_inputs(self)
        if self._input is None: self._input = numpy.zeros(self.neurons)
        self._input[:] = self.Jbias

    def _transmit_rate_direct(self, conn):
        x = self.activity_to_array(self._output,
                                   decoder=self.get_decoder(conn.func))
        conn.pop2._input += conn.apply_weight(x)

    def _transmit_rate_rate(self, conn):
        x = self.activity_to_array(self._output,
                                   decoder=self.get_decoder(conn.func))
        x = conn.apply_weight(x)
        conn.pop2._input += conn.pop2.array_to_current(x)

    def _transmit_direct_rate(self, conn):
        conn.pop2._input += conn.pop2.array_to_current(
            conn.apply_func_weight(self._output))

    def initialize_node(self):
        random = numpy.random.RandomState(seed=self.seed)

        if self.data_saturations is None:
            sr = self.saturation_range
            sat = random.uniform(sr[0], sr[1], (self.neurons, 1))
        else:
            N = len(self.data_saturations)
            sat = numpy.array(
                [[self.data_saturations[i % N] for i in range(self.neurons)]],
                dtype=numpy.dtype('float32')).T

        if self.data_thresholds is None:
            delta = (self.max - self.min) * (1 - self.threshold_coverage) * 0.5
            min_thresh = self.min + delta
            max_thresh = self.max - delta
            if self.threshold_min is not None: min_thresh = self.threshold_min
            if self.threshold_max is not None: max_thresh = self.threshold_max

            thresh = random.uniform(min_thresh, max_thresh, (self.neurons, 1))
        else:
            N = len(self.data_thresholds)
            thresh = numpy.array(
                [[self.data_thresholds[i % N] for i in range(self.neurons)]],
                dtype=numpy.dtype('float32')).T

        self.initialize_neurons(sat, thresh)

        if self.data_basis is None:
            g = makeGenerator(self.basis_style, self.dimensions,
                              int(random.randint(0x7FFFFFFF)))
            self.basis = g.get(self.neurons).T
        else:
            N = len(self.data_basis)
            self.basis = numpy.array(
                [self.data_basis[i % N] for i in range(self.neurons)],
                dtype=numpy.dtype('float32'))
            if len(self.basis.shape) == 1:
                self.basis.shape = (self.neurons, self.dimensions)

        self.sample_generator = makeGenerator(self.sample_style,
                                              self.dimensions,
                                              int(random.randint(0x7FFFFFFF)))
        if self.min != -1 or self.max != 1:
            scale = (self.max - self.min) / 2.0
            if scale != 1.0: self.sample_generator.scale = scale
            offset = (self.max + self.min) / 2.0
            if scale != 0.0: self.sample_generator.offset = offset

    def initialize_neurons(self, saturations, thresholds):
        saturations = numpy.array(saturations, dtype=numpy.float32)
        thresholds = numpy.array(thresholds, dtype=numpy.float32)
        x1, y1 = thresholds, numpy.zeros((self.neurons, 1),
                                         dtype=numpy.float32)
        x2, y2 = self.max, saturations
        if not self.lif:
            m = (y1 - y2) / (x1 - x2)
            b = y1 - m * x1
        else:
            numpy.seterr(divide='ignore')
            z1 = numpy.where(
                y1 <= 0, 1.0, 1.0 / (1 - numpy.exp(
                    (self.t_ref - (1.0 / y1)) / self.t_rc)))
            z2 = numpy.where(
                y2 <= 0, 1.0, 1.0 / (1 - numpy.exp(
                    (self.t_ref - (1.0 / y2)) / self.t_rc)))
            numpy.seterr(divide='warn')
            m = (z1 - z2) / (x1 - x2)
            b = z1 - m * x1
        self.alpha, self.Jbias = m, b
        self.Jbias.shape = self.Jbias.shape[0]
        self.alpha.shape = self.alpha.shape[0]

    def current_to_activity(self, J):
        if not self.lif:
            return numpy.maximum(J, 0)
        else:
            J = numpy.maximum(J, 0)
            numpy.seterr(invalid='ignore', divide='ignore')
            G = self.t_ref - self.t_rc * numpy.log(1 - self.J_threshold / J)
            G = numpy.where(G > 0.001, 1 / G, 0)
            numpy.seterr(invalid='warn', divide='warn')
            return G

    def array_to_current(self, array):
        b = self.basis
        phi_x = numpy.dot(b, array)
        J = self.alpha * phi_x
        return J

    def arrays_to_currents(self, arrays):
        b = self.basis
        phi_x = numpy.dot(b, arrays)
        J = self.alpha * phi_x.T
        return J.T

    def activity_to_array(self, activity, decoder=None):
        if activity is None: activity = numpy.zeros(self.neurons)
        if decoder is None:
            decoder = self.get_decoder()
        array = numpy.dot(activity.T, decoder)
        return array

    def add_activation_noise(self, actv, noise=None):
        if noise is None: noise = self.activation_noise
        if noise > 0:
            actv = numpy.random.normal(actv, self.saturation_range[1] * noise)
            actv = numpy.maximum(0, actv)
        return actv

    def get_decoder(self, func=None, noise=None):
        if noise is None: noise = self.activation_noise

        name = ''
        name_without_noise = ''
        if func:
            hash_info = make_hash_info(func)
            name = '-%s-%08x' % (func.__name__, hash(tuple(hash_info))
                                 )  #hash(tuple(func_id)))
            name = name.replace('<', '_').replace('>', '_')
            #print 'name',name
            name_without_noise = name
        name += '-%4.2f' % noise

        if name in self.decoders: return self.decoders[name]
        decoder = self.storage.get('decoder' + name, (self.neurons, -1))
        if decoder is not None:
            self.decoders[name] = decoder
            return decoder

        warning = False
        if self.neurons > self.decoder_size_warning:
            warning = True
            print 'Warning: calculating decoder for size %d neural group.' % self.neurons
            if self.neurons > self.decoder_size_limit:
                print '  Gamma matrices will be created, but they are too large for one machine to invert.'
            else:
                print '  This may take a few minutes.'

        noise *= self.saturation_range[1]

        upsilon = None
        upsilon = self.storage.get('upsilon' + name_without_noise,
                                   (self.neurons, -1))

        gamma_inv = None
        need_gamma = True
        gamma_s = self.storage.get('gamma.s', self.neurons)
        if gamma_s is not None:
            gamma_v = self.storage.get('gamma.v', (self.neurons, self.neurons))
            if svd_limit is not None:
                gamma_s = gamma_s[gamma_s > gamma_s[0] * svd_limit]
                gamma_v = gamma_v[:len(gamma_s), :]
            s_inv = numpy.diag(1.0 /
                               (gamma_s + noise * noise * self.sample_count))
            gamma_inv = numpy.dot(numpy.dot(gamma_v.T, s_inv), gamma_v)
            need_gamma = False
        else:
            gamma = self.storage.get('gamma', (self.neurons, self.neurons))
            if gamma is not None: need_gamma = False

        if need_gamma or upsilon is None:
            if self.dimensions >= 3 and self.use_hd:
                gamma, moments = calc_gamma_moments(self, dr=0.01)
                gamma *= self.sample_count
                ups = self.basis * moments[1].reshape(
                    (moments[1].shape[0], 1)) * self.sample_count

            else:

                self.sample_generator.reset()
                count = self.sample_count
                ups = None
                while count > 0:
                    s = min(count, self.sample_step_size)
                    if not self.sample_generator.can_continue(self.dimensions):
                        s = count
                    if warning:
                        print 'processing %d of %d samples (%d left)' % (
                            s, self.sample_count, count)
                    samples = self.sample_generator.get(s)
                    count -= s

                    curr = self.arrays_to_currents(samples)
                    curr = curr.T + self.Jbias
                    actv = self.current_to_activity(curr.T)
                    #actv=self.array_to_activity(samples)

                    if need_gamma:
                        g = numpy.dot(actv, actv.T)
                        if gamma is None: gamma = g
                        else: gamma += g

                    if upsilon is None:
                        samples = samples.T
                        if func is not None:
                            if self.dimensions == 1:
                                samples = samples[:, 0]
                            samples = numpy.array([
                                self.value_to_array(
                                    func(self.array_to_value(x)))
                                for x in samples
                            ],
                                                  dtype=numpy.float32)
                        u = numpy.dot(actv, samples)
                        if ups is None: ups = u
                        else: ups += u
            if need_gamma:
                self.storage.set('gamma', gamma)
            if upsilon is None:
                upsilon = ups
                self.storage.set('upsilon' + name_without_noise, upsilon)

        error_flag = False
        if gamma_inv is None:
            if gamma.shape[0] > self.decoder_size_limit:
                print 'Need other program to invert ' + self.storage.path(
                    'gamma')
                gamma_inv = numpy.zeros(gamma.shape, dtype=numpy.float32)
                error_flag = True
            else:
                if noise > 0:
                    gamma += numpy.identity(
                        gamma.shape[0]) * (noise * noise) * self.sample_count
                if gamma.shape[0] > self.decoder_size_warning:
                    print 'inverting %dx%d gamma matrix' % gamma.shape
                gamma_inv = numpy.linalg.pinv(gamma)

        decoder = numpy.dot(gamma_inv, upsilon)
        if len(decoder.shape) == 1:
            decoder.shape = decoder.shape[0], 1

        self.decoders[name] = decoder
        if not error_flag:
            self.storage.set('decoder' + name, decoder)
        return decoder