コード例 #1
0
    def distance2(self, graph1, graph2, permutation):
        """
        Compute a graph distance metric between two graphs give a permutation 
        vector. This is given by F(P) = (1-alpha)/(||W1||^2_F + ||W2||^2_F)
        (||W1 - P W2 P.T||^2_F) - alpha 1/(||V1||_F^2 + ||V2||_F^2) ||V1 - P.T V2||^2_F 
        and is bounded between 0 and 1. 
        
        :param graph1: A graph object 
        
        :param graph2: The second graph object to match 
        
        :param permutation: An array of permutation indices matching the first to second graph 
        :type permutation: `numpy.ndarray`
        
        """
        if self.useWeightM:
            W1 = graph1.getWeightMatrix()
            W2 = graph2.getWeightMatrix()
        else:
            W1 = graph1.adjacencyMatrix()
            W2 = graph2.adjacencyMatrix()

        if W1.shape[0] < W2.shape[0]:
            W1 = Util.extendArray(W1, W2.shape)
        elif W2.shape[0] < W1.shape[0]:
            W2 = Util.extendArray(W2, W1.shape)

        n = W1.shape[0]
        P = numpy.zeros((n, n))
        P[(numpy.arange(n), permutation)] = 1
        dist1 = numpy.linalg.norm(W1 - P.dot(W2).dot(P.T))**2

        #Now compute the vertex similarities distance
        V1 = graph1.getVertexList().getVertices()
        V2 = graph2.getVertexList().getVertices()

        if V1.shape[0] < V2.shape[0]:
            V1 = Util.extendArray(V1, V2.shape)
        elif V2.shape[0] < V1.shape[0]:
            V2 = Util.extendArray(V2, V1.shape)

        dist2 = numpy.sum((V1 - P.T.dot(V2))**2)

        norm1 = ((W1**2).sum() + (W2**2).sum())
        norm2 = ((V1**2).sum() + (V2**2).sum())

        if norm1 != 0:
            dist1 = dist1 / norm1
        if norm2 != 0:
            dist2 = dist2 / norm2

        dist = (1 - self.alpha) * dist1 + self.alpha * dist2

        return dist
コード例 #2
0
ファイル: GraphMatch.py プロジェクト: kentwang/sandbox
    def distance2(self, graph1, graph2, permutation):
        """
        Compute a graph distance metric between two graphs give a permutation 
        vector. This is given by F(P) = (1-alpha)/(||W1||^2_F + ||W2||^2_F)
        (||W1 - P W2 P.T||^2_F) - alpha 1/(||V1||_F^2 + ||V2||_F^2) ||V1 - P.T V2||^2_F 
        and is bounded between 0 and 1. 
        
        :param graph1: A graph object 
        
        :param graph2: The second graph object to match 
        
        :param permutation: An array of permutation indices matching the first to second graph 
        :type permutation: `numpy.ndarray`
        
        """
        if self.useWeightM:
            W1 = graph1.getWeightMatrix()
            W2 = graph2.getWeightMatrix()
        else:
            W1 = graph1.adjacencyMatrix()
            W2 = graph2.adjacencyMatrix()

        if W1.shape[0] < W2.shape[0]:
            W1 = Util.extendArray(W1, W2.shape)
        elif W2.shape[0] < W1.shape[0]:
            W2 = Util.extendArray(W2, W1.shape)

        n = W1.shape[0]
        P = numpy.zeros((n, n))
        P[(numpy.arange(n), permutation)] = 1
        dist1 = numpy.linalg.norm(W1 - P.dot(W2).dot(P.T)) ** 2

        # Now compute the vertex similarities distance
        V1 = graph1.getVertexList().getVertices()
        V2 = graph2.getVertexList().getVertices()

        if V1.shape[0] < V2.shape[0]:
            V1 = Util.extendArray(V1, V2.shape)
        elif V2.shape[0] < V1.shape[0]:
            V2 = Util.extendArray(V2, V1.shape)

        dist2 = numpy.sum((V1 - P.T.dot(V2)) ** 2)

        norm1 = (W1 ** 2).sum() + (W2 ** 2).sum()
        norm2 = (V1 ** 2).sum() + (V2 ** 2).sum()

        if norm1 != 0:
            dist1 = dist1 / norm1
        if norm2 != 0:
            dist2 = dist2 / norm2

        dist = (1 - self.alpha) * dist1 + self.alpha * dist2

        return dist
コード例 #3
0
ファイル: UtilTest.py プロジェクト: charanpald/sandbox
 def testExtendArray(self): 
     X = numpy.random.rand(5, 5)
     X2 = Util.extendArray(X, (10, 5))
     
     nptst.assert_array_equal(X, X2[0:5, :])
     nptst.assert_array_equal(0, X2[5:, :])          
     
     X2 = Util.extendArray(X, (10, 5), 1.23)
     
     nptst.assert_array_equal(X, X2[0:5, :])
     nptst.assert_array_equal(1.23, X2[5:, :])  
     
     #Now try extending using an array 
     X2 = Util.extendArray(X, (10, 5), numpy.array([1, 2, 3, 4, 5]))
     nptst.assert_array_equal(X, X2[0:5, :])
     
     for i in range(5, 10): 
         nptst.assert_array_equal(numpy.array([1, 2, 3, 4, 5]), X2[i, :])          
コード例 #4
0
    def testExtendArray(self):
        X = numpy.random.rand(5, 5)
        X2 = Util.extendArray(X, (10, 5))

        nptst.assert_array_equal(X, X2[0:5, :])
        nptst.assert_array_equal(0, X2[5:, :])

        X2 = Util.extendArray(X, (10, 5), 1.23)

        nptst.assert_array_equal(X, X2[0:5, :])
        nptst.assert_array_equal(1.23, X2[5:, :])

        #Now try extending using an array
        X2 = Util.extendArray(X, (10, 5), numpy.array([1, 2, 3, 4, 5]))
        nptst.assert_array_equal(X, X2[0:5, :])

        for i in range(5, 10):
            nptst.assert_array_equal(numpy.array([1, 2, 3, 4, 5]), X2[i, :])
コード例 #5
0
ファイル: GraphMatch.py プロジェクト: kentwang/sandbox
    def distance(self, graph1, graph2, permutation, normalised=False, nonNeg=False, verbose=False):
        """
        Compute the graph distance metric between two graphs given a permutation 
        vector. This is given by F(P) = (1-alpha)/(||W1||^2_F + ||W2||^2_F)(||W1 - P W2 P.T||^2_F)
        - alpha 1/||C||_F tr(C.T P) in the normalised case. If we want an unnormalised 
        solution it is computed as (1-alpha)/(||W1 - P W2 P.T||^2_F) - alpha tr C.T P 
        and finally there is a standardised case in which the distance is between 
        0 and 1, where ||C||_F is used to normalise the vertex similarities and 
        we assume 0 <= C_ij <= 1. 
        
        :param graph1: A graph object 
        
        :param graph2: The second graph object to match 
        
        :param permutation: An array of permutation indices matching the first to second graph 
        :type permutation: `numpy.ndarray`
        
        :param normalised: Specify whether to normalise the objective function 
        :type normalised: `bool`
        
        :param nonNeg: Specify whether we want a non-negative solution.  
        :type nonNeg: `bool`
        
        :param verbose: Specify whether to return graph and label distance 
        :type nonNeg: `bool`
        """
        if graph1.size == 0 and graph2.size == 0:
            if not verbose:
                return 0.0
            else:
                return 0.0, 0.0, 0.0
        elif graph1.size == 0 or graph2.size == 0:
            if normalised:
                if not verbose:
                    return 1 - self.alpha
                else:
                    return 1 - self.alpha, 1 - self.alpha, 0.0
            else:
                raise ValueError("Unsupported case")

        if self.useWeightM:
            W1 = graph1.getWeightMatrix()
            W2 = graph2.getWeightMatrix()
        else:
            W1 = graph1.adjacencyMatrix()
            W2 = graph2.adjacencyMatrix()

        if W1.shape[0] < W2.shape[0]:
            W1 = Util.extendArray(W1, W2.shape, self.rho)
        elif W2.shape[0] < W1.shape[0]:
            W2 = Util.extendArray(W2, W1.shape, self.rho)

        n = W1.shape[0]
        P = numpy.zeros((n, n))
        P[(numpy.arange(n), permutation)] = 1
        dist1 = numpy.linalg.norm(W1 - P.dot(W2).dot(P.T)) ** 2

        # Now compute the vertex similarities trace
        C = self.vertexSimilarities(graph1, graph2)
        minC = numpy.min(C)
        maxC = numpy.max(C)
        C = Util.extendArray(C, (n, n), minC + self.gamma * (maxC - minC))

        dist2 = numpy.trace(C.T.dot(P))

        if normalised:
            norm1 = (W1 ** 2).sum() + (W2 ** 2).sum()
            norm2 = numpy.linalg.norm(C)
            if norm1 != 0:
                dist1 = dist1 / norm1
            if norm2 != 0:
                dist2 = dist2 / norm2

        dist = (1 - self.alpha) * dist1 - self.alpha * dist2

        # If nonNeg = True then we add a term to the distance to ensure it is
        # always positive. The numerator is an upper bound on tr(C.T P)
        if nonNeg and normalised:
            normC = norm2

            logging.debug(
                "Graph distance: "
                + str(dist1)
                + " label distance: "
                + str(dist2)
                + " distance offset: "
                + str(self.alpha * n / normC)
                + " graph sizes: "
                + str((graph1.size, graph2.size))
            )

            if normC != 0:
                dist = dist + self.alpha * n / normC
        else:
            logging.debug(
                "Graph objective: "
                + str(dist1)
                + " label objective: "
                + str(dist2)
                + " weighted objective: "
                + str(dist)
                + " graph sizes: "
                + str((graph1.size, graph2.size))
            )

        if verbose:
            return dist, dist1, dist2
        else:
            return dist
コード例 #6
0
    def distance(self,
                 graph1,
                 graph2,
                 permutation,
                 normalised=False,
                 nonNeg=False,
                 verbose=False):
        """
        Compute the graph distance metric between two graphs given a permutation 
        vector. This is given by F(P) = (1-alpha)/(||W1||^2_F + ||W2||^2_F)(||W1 - P W2 P.T||^2_F)
        - alpha 1/||C||_F tr(C.T P) in the normalised case. If we want an unnormalised 
        solution it is computed as (1-alpha)/(||W1 - P W2 P.T||^2_F) - alpha tr C.T P 
        and finally there is a standardised case in which the distance is between 
        0 and 1, where ||C||_F is used to normalise the vertex similarities and 
        we assume 0 <= C_ij <= 1. 
        
        :param graph1: A graph object 
        
        :param graph2: The second graph object to match 
        
        :param permutation: An array of permutation indices matching the first to second graph 
        :type permutation: `numpy.ndarray`
        
        :param normalised: Specify whether to normalise the objective function 
        :type normalised: `bool`
        
        :param nonNeg: Specify whether we want a non-negative solution.  
        :type nonNeg: `bool`
        
        :param verbose: Specify whether to return graph and label distance 
        :type nonNeg: `bool`
        """
        if graph1.size == 0 and graph2.size == 0:
            if not verbose:
                return 0.0
            else:
                return 0.0, 0.0, 0.0
        elif graph1.size == 0 or graph2.size == 0:
            if normalised:
                if not verbose:
                    return 1 - self.alpha
                else:
                    return 1 - self.alpha, 1 - self.alpha, 0.0
            else:
                raise ValueError("Unsupported case")

        if self.useWeightM:
            W1 = graph1.getWeightMatrix()
            W2 = graph2.getWeightMatrix()
        else:
            W1 = graph1.adjacencyMatrix()
            W2 = graph2.adjacencyMatrix()

        if W1.shape[0] < W2.shape[0]:
            W1 = Util.extendArray(W1, W2.shape, self.rho)
        elif W2.shape[0] < W1.shape[0]:
            W2 = Util.extendArray(W2, W1.shape, self.rho)

        n = W1.shape[0]
        P = numpy.zeros((n, n))
        P[(numpy.arange(n), permutation)] = 1
        dist1 = numpy.linalg.norm(W1 - P.dot(W2).dot(P.T))**2

        #Now compute the vertex similarities trace
        C = self.vertexSimilarities(graph1, graph2)
        minC = numpy.min(C)
        maxC = numpy.max(C)
        C = Util.extendArray(C, (n, n), minC + self.gamma * (maxC - minC))

        dist2 = numpy.trace(C.T.dot(P))

        if normalised:
            norm1 = ((W1**2).sum() + (W2**2).sum())
            norm2 = numpy.linalg.norm(C)
            if norm1 != 0:
                dist1 = dist1 / norm1
            if norm2 != 0:
                dist2 = dist2 / norm2

        dist = (1 - self.alpha) * dist1 - self.alpha * dist2

        #If nonNeg = True then we add a term to the distance to ensure it is
        #always positive. The numerator is an upper bound on tr(C.T P)
        if nonNeg and normalised:
            normC = norm2

            logging.debug("Graph distance: " + str(dist1) +
                          " label distance: " + str(dist2) +
                          " distance offset: " + str(self.alpha * n / normC) +
                          " graph sizes: " + str((graph1.size, graph2.size)))

            if normC != 0:
                dist = dist + self.alpha * n / normC
        else:
            logging.debug("Graph objective: " + str(dist1) +
                          " label objective: " + str(dist2) +
                          " weighted objective: " + str(dist) +
                          " graph sizes: " + str((graph1.size, graph2.size)))

        if verbose:
            return dist, dist1, dist2
        else:
            return dist
コード例 #7
0
            def next(self):
                X = self.XIterator.next()
                logging.debug("Learning on matrix with shape: " +
                              str(X.shape) + " and " + str(X.nnz) +
                              " non-zeros")

                if self.iterativeSoftImpute.weighted:
                    #Compute row and col probabilities
                    up, vp = SparseUtils.nonzeroRowColsProbs(X)
                    nzuInds = up == 0
                    nzvInds = vp == 0
                    u = numpy.sqrt(1 / (up + numpy.array(nzuInds, numpy.int)))
                    v = numpy.sqrt(1 / (vp + numpy.array(nzvInds, numpy.int)))
                    u[nzuInds] = 0
                    v[nzvInds] = 0

                if self.rhos != None:
                    self.iterativeSoftImpute.setRho(self.rhos.next())

                if not scipy.sparse.isspmatrix_csc(X):
                    raise ValueError("X must be a csc_matrix not " +
                                     str(type(X)))

                #Figure out what lambda should be
                #PROPACK has problems with convergence
                Y = scipy.sparse.csc_matrix(X, dtype=numpy.float)
                U, s, V = ExpSU.SparseUtils.svdArpack(Y, 1, kmax=20)
                del Y
                #U, s, V = SparseUtils.svdPropack(X, 1, kmax=20)
                maxS = s[0]
                logging.debug("Largest singular value : " + str(maxS))

                (n, m) = X.shape

                if self.j == 0:
                    self.oldU = numpy.zeros((n, 1))
                    self.oldS = numpy.zeros(1)
                    self.oldV = numpy.zeros((m, 1))
                else:
                    oldN = self.oldU.shape[0]
                    oldM = self.oldV.shape[0]

                    if self.iterativeSoftImpute.updateAlg == "initial":
                        if n > oldN:
                            self.oldU = Util.extendArray(
                                self.oldU, (n, self.oldU.shape[1]))
                        elif n < oldN:
                            self.oldU = self.oldU[0:n, :]

                        if m > oldM:
                            self.oldV = Util.extendArray(
                                self.oldV, (m, self.oldV.shape[1]))
                        elif m < oldN:
                            self.oldV = self.oldV[0:m, :]
                    elif self.iterativeSoftImpute.updateAlg == "zero":
                        self.oldU = numpy.zeros((n, 1))
                        self.oldS = numpy.zeros(1)
                        self.oldV = numpy.zeros((m, 1))
                    else:
                        raise ValueError("Unknown SVD update algorithm: " +
                                         self.updateAlg)

                rowInds, colInds = X.nonzero()

                gamma = self.iterativeSoftImpute.eps + 1
                i = 0

                self.iterativeSoftImpute.measures = numpy.zeros(
                    (self.iterativeSoftImpute.maxIterations, 4))

                while gamma > self.iterativeSoftImpute.eps:
                    if i == self.iterativeSoftImpute.maxIterations:
                        logging.debug("Maximum number of iterations reached")
                        break

                    ZOmega = SparseUtilsCython.partialReconstructPQ(
                        (rowInds, colInds), self.oldU * self.oldS, self.oldV)
                    Y = X - ZOmega
                    #Y = Y.tocsc()
                    #del ZOmega
                    Y = csarray(Y, storagetype="row")
                    gc.collect()

                    #os.system('taskset -p 0xffffffff %d' % os.getpid())

                    if self.iterativeSoftImpute.svdAlg == "propack":
                        L = LinOperatorUtils.sparseLowRankOp(Y,
                                                             self.oldU,
                                                             self.oldS,
                                                             self.oldV,
                                                             parallel=False)
                        newU, newS, newV = SparseUtils.svdPropack(
                            L,
                            k=self.iterativeSoftImpute.k,
                            kmax=self.iterativeSoftImpute.kmax)
                    elif self.iterativeSoftImpute.svdAlg == "arpack":
                        L = LinOperatorUtils.sparseLowRankOp(Y,
                                                             self.oldU,
                                                             self.oldS,
                                                             self.oldV,
                                                             parallel=False)
                        newU, newS, newV = SparseUtils.svdArpack(
                            L,
                            k=self.iterativeSoftImpute.k,
                            kmax=self.iterativeSoftImpute.kmax)
                    elif self.iterativeSoftImpute.svdAlg == "svdUpdate":
                        newU, newS, newV = SVDUpdate.addSparseProjected(
                            self.oldU, self.oldS, self.oldV, Y,
                            self.iterativeSoftImpute.k)
                    elif self.iterativeSoftImpute.svdAlg == "rsvd":
                        L = LinOperatorUtils.sparseLowRankOp(Y,
                                                             self.oldU,
                                                             self.oldS,
                                                             self.oldV,
                                                             parallel=True)
                        newU, newS, newV = RandomisedSVD.svd(
                            L,
                            self.iterativeSoftImpute.k,
                            p=self.iterativeSoftImpute.p,
                            q=self.iterativeSoftImpute.q)
                    elif self.iterativeSoftImpute.svdAlg == "rsvdUpdate":
                        L = LinOperatorUtils.sparseLowRankOp(Y,
                                                             self.oldU,
                                                             self.oldS,
                                                             self.oldV,
                                                             parallel=True)
                        if self.j == 0:
                            newU, newS, newV = RandomisedSVD.svd(
                                L,
                                self.iterativeSoftImpute.k,
                                p=self.iterativeSoftImpute.p,
                                q=self.iterativeSoftImpute.q)
                        else:
                            newU, newS, newV = RandomisedSVD.svd(
                                L,
                                self.iterativeSoftImpute.k,
                                p=self.iterativeSoftImpute.p,
                                q=self.iterativeSoftImpute.qu,
                                omega=self.oldV)
                    elif self.iterativeSoftImpute.svdAlg == "rsvdUpdate2":

                        if self.j == 0:
                            L = LinOperatorUtils.sparseLowRankOp(Y,
                                                                 self.oldU,
                                                                 self.oldS,
                                                                 self.oldV,
                                                                 parallel=True)
                            newU, newS, newV = RandomisedSVD.svd(
                                L,
                                self.iterativeSoftImpute.k,
                                p=self.iterativeSoftImpute.p,
                                q=self.iterativeSoftImpute.q)
                        else:
                            #Need linear operator which is U s V
                            L = LinOperatorUtils.lowRankOp(
                                self.oldU, self.oldS, self.oldV)
                            Y = GeneralLinearOperator.asLinearOperator(
                                Y, parallel=True)
                            newU, newS, newV = RandomisedSVD.updateSvd(
                                L,
                                self.oldU,
                                self.oldS,
                                self.oldV,
                                Y,
                                self.iterativeSoftImpute.k,
                                p=self.iterativeSoftImpute.p)
                    else:
                        raise ValueError("Unknown SVD algorithm: " +
                                         self.iterativeSoftImpute.svdAlg)

                    if self.iterativeSoftImpute.weighted and i == 0:
                        delta = numpy.diag((u * newU.T).dot(newU))
                        pi = numpy.diag((v * newV.T).dot(newV))
                        lmbda = (maxS / numpy.max(
                            delta * pi)) * self.iterativeSoftImpute.rho
                        lmbdav = lmbda * delta * pi
                    elif not self.iterativeSoftImpute.weighted:
                        lmbda = maxS * self.iterativeSoftImpute.rho
                        if i == 0:
                            logging.debug("lambda: " + str(lmbda))
                        lmbdav = lmbda

                    newS = newS - lmbdav
                    #Soft threshold
                    newS = numpy.clip(newS, 0, numpy.max(newS))

                    normOldZ = (self.oldS**2).sum()
                    normNewZmOldZ = (self.oldS**2).sum() + (
                        newS**2).sum() - 2 * numpy.trace(
                            (self.oldV.T.dot(newV * newS)).dot(
                                newU.T.dot(self.oldU * self.oldS)))

                    #We can get newZ == oldZ in which case we break
                    if normNewZmOldZ < self.tol:
                        gamma = 0
                    elif abs(normOldZ) < self.tol:
                        gamma = self.iterativeSoftImpute.eps + 1
                    else:
                        gamma = normNewZmOldZ / normOldZ

                    if self.iterativeSoftImpute.verbose:
                        theta1 = (
                            self.iterativeSoftImpute.k -
                            numpy.linalg.norm(self.oldU.T.dot(newU), 'fro')**
                            2) / self.iterativeSoftImpute.k
                        theta2 = (
                            self.iterativeSoftImpute.k -
                            numpy.linalg.norm(self.oldV.T.dot(newV), 'fro')**
                            2) / self.iterativeSoftImpute.k
                        thetaS = numpy.linalg.norm(
                            newS - self.oldS)**2 / numpy.linalg.norm(newS)**2
                        self.iterativeSoftImpute.measures[i, :] = numpy.array(
                            [gamma, theta1, theta2, thetaS])

                    self.oldU = newU.copy()
                    self.oldS = newS.copy()
                    self.oldV = newV.copy()

                    logging.debug("Iteration " + str(i) + " gamma=" +
                                  str(gamma))
                    i += 1

                if self.iterativeSoftImpute.postProcess:
                    #Add the mean vectors
                    previousS = newS
                    newU = numpy.c_[newU, numpy.array(X.mean(1)).ravel()]
                    newV = numpy.c_[newV, numpy.array(X.mean(0)).ravel()]
                    newS = self.iterativeSoftImpute.unshrink(X, newU, newV)

                    #Note that this increases the rank of U and V by 1
                    #print("Difference in s after postprocessing: " + str(numpy.linalg.norm(previousS - newS[0:-1])))
                    logging.debug("Difference in s after postprocessing: " +
                                  str(numpy.linalg.norm(previousS -
                                                        newS[0:-1])))

                logging.debug("Number of iterations for rho=" +
                              str(self.iterativeSoftImpute.rho) + ": " +
                              str(i))
                self.j += 1
                return (newU, newS, newV)
コード例 #8
0
            def next(self):
                X = self.XIterator.next()
                logging.debug("Learning on matrix with shape: " + str(X.shape) + " and " + str(X.nnz) + " non-zeros")    
                
                if self.iterativeSoftImpute.weighted: 
                    #Compute row and col probabilities 
                    up, vp = SparseUtils.nonzeroRowColsProbs(X)
                    nzuInds = up==0
                    nzvInds = vp==0
                    u = numpy.sqrt(1/(up + numpy.array(nzuInds, numpy.int))) 
                    v = numpy.sqrt(1/(vp + numpy.array(nzvInds, numpy.int)))
                    u[nzuInds] = 0 
                    v[nzvInds] = 0 
                
                if self.rhos != None: 
                    self.iterativeSoftImpute.setRho(self.rhos.next())

                if not scipy.sparse.isspmatrix_csc(X):
                    raise ValueError("X must be a csc_matrix not " + str(type(X)))
                    
                #Figure out what lambda should be 
                #PROPACK has problems with convergence 
                Y = scipy.sparse.csc_matrix(X, dtype=numpy.float)
                U, s, V = ExpSU.SparseUtils.svdArpack(Y, 1, kmax=20)
                del Y
                #U, s, V = SparseUtils.svdPropack(X, 1, kmax=20)
                maxS = s[0]
                logging.debug("Largest singular value : " + str(maxS))

                (n, m) = X.shape

                if self.j == 0:
                    self.oldU = numpy.zeros((n, 1))
                    self.oldS = numpy.zeros(1)
                    self.oldV = numpy.zeros((m, 1))
                else:
                    oldN = self.oldU.shape[0]
                    oldM = self.oldV.shape[0]

                    if self.iterativeSoftImpute.updateAlg == "initial":
                        if n > oldN:
                            self.oldU = Util.extendArray(self.oldU, (n, self.oldU.shape[1]))
                        elif n < oldN:
                            self.oldU = self.oldU[0:n, :]

                        if m > oldM:
                            self.oldV = Util.extendArray(self.oldV, (m, self.oldV.shape[1]))
                        elif m < oldN:
                            self.oldV = self.oldV[0:m, :]
                    elif self.iterativeSoftImpute.updateAlg == "zero":
                        self.oldU = numpy.zeros((n, 1))
                        self.oldS = numpy.zeros(1)
                        self.oldV = numpy.zeros((m, 1))
                    else:
                        raise ValueError("Unknown SVD update algorithm: " + self.updateAlg)

                rowInds, colInds = X.nonzero()

                gamma = self.iterativeSoftImpute.eps + 1
                i = 0

                self.iterativeSoftImpute.measures = numpy.zeros((self.iterativeSoftImpute.maxIterations, 4))

                while gamma > self.iterativeSoftImpute.eps:
                    if i == self.iterativeSoftImpute.maxIterations: 
                        logging.debug("Maximum number of iterations reached")
                        break 
                    
                    ZOmega = SparseUtilsCython.partialReconstructPQ((rowInds, colInds), self.oldU*self.oldS, self.oldV)
                    Y = X - ZOmega
                    #Y = Y.tocsc()
                    #del ZOmega
                    Y = csarray(Y, storagetype="row")
                    gc.collect()
                    
                    #os.system('taskset -p 0xffffffff %d' % os.getpid())

                    if self.iterativeSoftImpute.svdAlg=="propack":
                        L = LinOperatorUtils.sparseLowRankOp(Y, self.oldU, self.oldS, self.oldV, parallel=False)                        
                        newU, newS, newV = SparseUtils.svdPropack(L, k=self.iterativeSoftImpute.k, kmax=self.iterativeSoftImpute.kmax)
                    elif self.iterativeSoftImpute.svdAlg=="arpack":
                        L = LinOperatorUtils.sparseLowRankOp(Y, self.oldU, self.oldS, self.oldV, parallel=False)                        
                        newU, newS, newV = SparseUtils.svdArpack(L, k=self.iterativeSoftImpute.k, kmax=self.iterativeSoftImpute.kmax)
                    elif self.iterativeSoftImpute.svdAlg=="svdUpdate":
                        newU, newS, newV = SVDUpdate.addSparseProjected(self.oldU, self.oldS, self.oldV, Y, self.iterativeSoftImpute.k)
                    elif self.iterativeSoftImpute.svdAlg=="rsvd":
                        L = LinOperatorUtils.sparseLowRankOp(Y, self.oldU, self.oldS, self.oldV, parallel=True)
                        newU, newS, newV = RandomisedSVD.svd(L, self.iterativeSoftImpute.k, p=self.iterativeSoftImpute.p, q=self.iterativeSoftImpute.q)
                    elif self.iterativeSoftImpute.svdAlg=="rsvdUpdate": 
                        L = LinOperatorUtils.sparseLowRankOp(Y, self.oldU, self.oldS, self.oldV, parallel=True)
                        if self.j == 0: 
                            newU, newS, newV = RandomisedSVD.svd(L, self.iterativeSoftImpute.k, p=self.iterativeSoftImpute.p, q=self.iterativeSoftImpute.q)
                        else: 
                            newU, newS, newV = RandomisedSVD.svd(L, self.iterativeSoftImpute.k, p=self.iterativeSoftImpute.p, q=self.iterativeSoftImpute.qu, omega=self.oldV)
                    elif self.iterativeSoftImpute.svdAlg=="rsvdUpdate2":
                        
                        if self.j == 0: 
                            L = LinOperatorUtils.sparseLowRankOp(Y, self.oldU, self.oldS, self.oldV, parallel=True)
                            newU, newS, newV = RandomisedSVD.svd(L, self.iterativeSoftImpute.k, p=self.iterativeSoftImpute.p, q=self.iterativeSoftImpute.q)
                        else: 
                            #Need linear operator which is U s V 
                            L = LinOperatorUtils.lowRankOp(self.oldU, self.oldS, self.oldV)
                            Y = GeneralLinearOperator.asLinearOperator(Y, parallel=True)
                            newU, newS, newV = RandomisedSVD.updateSvd(L, self.oldU, self.oldS, self.oldV, Y, self.iterativeSoftImpute.k, p=self.iterativeSoftImpute.p)
                    else:
                        raise ValueError("Unknown SVD algorithm: " + self.iterativeSoftImpute.svdAlg)

                    if self.iterativeSoftImpute.weighted and i==0: 
                        delta = numpy.diag((u*newU.T).dot(newU))
                        pi = numpy.diag((v*newV.T).dot(newV))
                        lmbda = (maxS/numpy.max(delta*pi))*self.iterativeSoftImpute.rho
                        lmbdav = lmbda*delta*pi
                    elif not self.iterativeSoftImpute.weighted: 
                        lmbda = maxS*self.iterativeSoftImpute.rho
                        if i==0: 
                            logging.debug("lambda: " + str(lmbda))
                        lmbdav = lmbda
                        
                    newS = newS - lmbdav                    
                    #Soft threshold
                    newS = numpy.clip(newS, 0, numpy.max(newS))
                    

                    normOldZ = (self.oldS**2).sum()
                    normNewZmOldZ = (self.oldS**2).sum() + (newS**2).sum() - 2*numpy.trace((self.oldV.T.dot(newV*newS)).dot(newU.T.dot(self.oldU*self.oldS)))

                    #We can get newZ == oldZ in which case we break
                    if normNewZmOldZ < self.tol:
                        gamma = 0
                    elif abs(normOldZ) < self.tol:
                        gamma = self.iterativeSoftImpute.eps + 1
                    else:
                        gamma = normNewZmOldZ/normOldZ
                        
                    if self.iterativeSoftImpute.verbose: 
                        theta1 = (self.iterativeSoftImpute.k - numpy.linalg.norm(self.oldU.T.dot(newU), 'fro')**2)/self.iterativeSoftImpute.k
                        theta2 = (self.iterativeSoftImpute.k - numpy.linalg.norm(self.oldV.T.dot(newV), 'fro')**2)/self.iterativeSoftImpute.k
                        thetaS = numpy.linalg.norm(newS - self.oldS)**2/numpy.linalg.norm(newS)**2
                        self.iterativeSoftImpute.measures[i, :] = numpy.array([gamma, theta1, theta2, thetaS])

                    self.oldU = newU.copy()
                    self.oldS = newS.copy()
                    self.oldV = newV.copy()

                    logging.debug("Iteration " + str(i) + " gamma="+str(gamma))
                    i += 1

                if self.iterativeSoftImpute.postProcess: 
                    #Add the mean vectors 
                    previousS = newS
                    newU = numpy.c_[newU, numpy.array(X.mean(1)).ravel()]
                    newV = numpy.c_[newV, numpy.array(X.mean(0)).ravel()]
                    newS = self.iterativeSoftImpute.unshrink(X, newU, newV)  
                    
                    #Note that this increases the rank of U and V by 1 
                    #print("Difference in s after postprocessing: " + str(numpy.linalg.norm(previousS - newS[0:-1]))) 
                    logging.debug("Difference in s after postprocessing: " + str(numpy.linalg.norm(previousS - newS[0:-1]))) 

                logging.debug("Number of iterations for rho="+str(self.iterativeSoftImpute.rho) + ": " + str(i))
                self.j += 1
                return (newU, newS, newV)