예제 #1
0
 def setUp(self):
     SP.random.seed(1)
     self.n = 4
     self.rank = 2
     self.C = limix.CLowRankCF(self.n, self.rank)
     self.name = 'CLowRankCF'
     self.n_params = self.C.getNumberParams()
     params = SP.exp(SP.randn(self.n_params))
     self.C.setParams(params)
예제 #2
0
파일: gp_clvm.py 프로젝트: jamesaliba/scLVM
    def __init__(self,
                 Y=None,
                 X0=None,
                 k=1,
                 standardize=False,
                 interaction=True):
        """
		Y:		data [NxG]
		X0:		known latent factors [Nxk0]
		k:		number of latent factors to infer
		"""

        assert Y != None, 'gpCLVM:: set Y!'
        assert X0 != None, 'gpCLVM:: set X0!'

        self.cache = {}
        self.interaction = interaction

        # read data
        self._setY(Y, standardize=standardize)
        self._setX0(X0)
        self.k = k

        # covariance for known latex factor
        self.C0 = limix.CFixedCF(self.K0)

        # covariance for unknow latent factor
        self.C = limix.CProductCF()
        self.Ca = limix.CLowRankCF(self.N, self.k)
        self.C.addCovariance(self.Ca)
        if self.interaction == True:
            self.Cb1 = limix.CFixedCF(SP.ones((self.N, self.N)))
            self.Cb1.setParamMask(SP.zeros(1))
            self.Cb2 = limix.CFixedCF(self.K0)
            self.Cb = limix.CSumCF()
            self.Cb.addCovariance(self.Cb1)
            self.Cb.addCovariance(self.Cb2)
            self.C.addCovariance(self.Cb)

        # total covariance
        covar = limix.CSumCF()
        covar.addCovariance(self.C0)
        covar.addCovariance(self.C)

        # likelihood
        self.ll = limix.CLikNormalIso()

        # init GP and hyper params
        self.gp = limix.CGPbase(covar, self.ll)
        self.gp.setY(self.Y)
예제 #3
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    def _buildTraitCovar(self,
                         trait_covar_type='lowrank_diag',
                         rank=1,
                         fixed_trait_covar=None,
                         jitter=1e-4):
        """
        Internal functions that builds the trait covariance matrix using the LIMIX framework

        Args:
            trait_covar_type: type of covaraince to use. Default 'freeform'. possible values are 
            rank:       rank of a possible lowrank component (default 1)
            fixed_trait_covar:   PxP matrix for the (predefined) trait-to-trait covariance matrix if fixed type is used
            jitter:        diagonal contribution added to trait-to-trait covariance matrices for regularization
        Returns:
            LIMIX::PCovarianceFunction for Trait covariance matrix
            vector labelling Cholesky parameters for different initializations
        """
        cov = limix.CSumCF()
        if trait_covar_type == 'freeform':
            cov.addCovariance(limix.CFreeFormCF(self.P))
            L = sp.eye(self.P)
            diag = sp.concatenate([L[i, :(i + 1)] for i in range(self.P)])
        elif trait_covar_type == 'fixed':
            assert fixed_trait_covar != None, 'VarianceDecomposition:: set fixed_trait_covar'
            assert fixed_trait_covar.shape[
                0] == self.N, 'VarianceDecomposition:: Incompatible shape for fixed_trait_covar'
            assert fixed_trait_covar.shape[
                1] == self.N, 'VarianceDecomposition:: Incompatible shape for fixed_trait_covar'
            cov.addCovariance(limix.CFixedCF(fixed_trait_covar))
            diag = sp.zeros(1)
        elif trait_covar_type == 'diag':
            cov.addCovariance(limix.CDiagonalCF(self.P))
            diag = sp.ones(self.P)
        elif trait_covar_type == 'lowrank':
            cov.addCovariance(limix.CLowRankCF(self.P, rank))
            diag = sp.zeros(self.P * rank)
        elif trait_covar_type == 'lowrank_id':
            cov.addCovariance(limix.CLowRankCF(self.P, rank))
            cov.addCovariance(limix.CFixedCF(sp.eye(self.P)))
            diag = sp.concatenate([sp.zeros(self.P * rank), sp.ones(1)])
        elif trait_covar_type == 'lowrank_diag':
            cov.addCovariance(limix.CLowRankCF(self.P, rank))
            cov.addCovariance(limix.CDiagonalCF(self.P))
            diag = sp.concatenate([sp.zeros(self.P * rank), sp.ones(self.P)])
        elif trait_covar_type == 'block':
            cov.addCovariance(limix.CFixedCF(sp.ones((self.P, self.P))))
            diag = sp.zeros(1)
        elif trait_covar_type == 'block_id':
            cov.addCovariance(limix.CFixedCF(sp.ones((self.P, self.P))))
            cov.addCovariance(limix.CFixedCF(sp.eye(self.P)))
            diag = sp.concatenate([sp.zeros(1), sp.ones(1)])
        elif trait_covar_type == 'block_diag':
            cov.addCovariance(limix.CFixedCF(sp.ones((self.P, self.P))))
            cov.addCovariance(limix.CDiagonalCF(self.P))
            diag = sp.concatenate([sp.zeros(1), sp.ones(self.P)])
        else:
            assert True == False, 'VarianceDecomposition:: trait_covar_type not valid'
        if jitter > 0:
            _cov = limix.CFixedCF(sp.eye(self.P))
            _cov.setParams(sp.array([sp.sqrt(jitter)]))
            _cov.setParamMask(sp.zeros(1))
            cov.addCovariance(_cov)
        return cov, diag
예제 #4
0
    def addMultiTraitTerm(self,
                          K=None,
                          covar_type='freeform',
                          is_noise=False,
                          normalize=True,
                          Ks=None,
                          offset=1e-4,
                          rank=1,
                          covar_K0=None):
        """
        add multi trait random effects term.
        The inter-trait covariance is parametrized by covar_type, where parameters are optimized.
        
        Args:
            K:      Individual-individual (Intra-Trait) Covariance Matrix [N, N]
                    (K is normalised in the C++ code such that K.trace()=N)
            covar_type: type of covaraince to use. Default 'freeform'. possible values are 
                            'freeform': free form optimization, 
                            'fixed': use a fixed matrix specified in covar_K0,
                            'diag': optimize a diagonal matrix, 
                            'lowrank': optimize a low rank matrix. The rank of the lowrank part is specified in the variable rank,
                            'lowrank_id': optimize a low rank matrix plus the weight of a constant diagonal matrix. The rank of the lowrank part is specified in the variable rank, 
                            'lowrank_diag': optimize a low rank matrix plus a free diagonal matrix. The rank of the lowrank part is specified in the variable rank, 
                            'block': optimize the weight of a constant P x P block matrix of ones,
                            'block_id': optimize the weight of a constant P x P block matrix of ones plus the weight of a constant diagonal matrix,
                            'block_diag': optimize the weight of a constant P x P block matrix of ones plus a free diagonal matrix,                            
            is_noise:   Boolean indicator specifying if the matrix is homoscedastic noise (weighted identity covariance) (default False)
            normalize:  Boolean indicator specifying if K is normalized such that K.trace()=N.
            Ks:			NxNtest cross covariance for predictions
            offset:		diagonal contribution added to trait-to-trait covariance matrices for regularization
            rank:       rank of a possible lowrank component (default 1)
            covar_K0:   PxP matrix for the (predefined) trait-to-trait covariance matrix if fixed type is used
        """
        assert self.P > 1, 'CVarianceDecomposition:: Incompatible number of traits'
        assert K != None or is_noise, 'CVarianceDecomposition:: Specify covariance structure'
        assert offset >= 0, 'CVarianceDecomposition:: offset must be >=0'

        #TODO: check that covar_K0 is correct if fixed typeCF is used..

        if is_noise:
            assert self.noisPos == None, 'CVarianceDecomposition:: noise term already exists'
            K = SP.eye(self.N)
            self.noisPos = self.n_terms
        else:
            assert K.shape[
                0] == self.N, 'CVarianceDecomposition:: Incompatible shape'
            assert K.shape[
                1] == self.N, 'CVarianceDecomposition:: Incompatible shape'

        if Ks != None:
            assert Ks.shape[
                0] == self.N, 'CVarianceDecomposition:: Incompatible shape'

        if normalize:
            Norm = 1 / K.diagonal().mean()
            K *= Norm
            if Ks != None: Ks *= Norm

        cov = limix.CSumCF()
        if covar_type == 'freeform':
            cov.addCovariance(limix.CFreeFormCF(self.P))
            L = SP.eye(self.P)
            diag = SP.concatenate([L[i, :(i + 1)] for i in range(self.P)])
        elif covar_type == 'fixed':
            cov.addCovariance(limix.CFixedCF(covar_K0))
            diag = SP.zeros(1)
        elif covar_type == 'diag':
            cov.addCovariance(limix.CDiagonalCF(self.P))
            diag = SP.ones(self.P)
        elif covar_type == 'lowrank':
            cov.addCovariance(limix.CLowRankCF(self.P, rank))
            diag = SP.zeros(self.P * rank)
        elif covar_type == 'lowrank_id':
            cov.addCovariance(limix.CLowRankCF(self.P, rank))
            cov.addCovariance(limix.CFixedCF(SP.eye(self.P)))
            diag = SP.concatenate([SP.zeros(self.P * rank), SP.ones(1)])
        elif covar_type == 'lowrank_diag':
            cov.addCovariance(limix.CLowRankCF(self.P, rank))
            cov.addCovariance(limix.CDiagonalCF(self.P))
            diag = SP.concatenate([SP.zeros(self.P * rank), SP.ones(self.P)])
        elif covar_type == 'block':
            cov.addCovariance(limix.CFixedCF(SP.ones((self.P, self.P))))
            diag = SP.zeros(1)
        elif covar_type == 'block_id':
            cov.addCovariance(limix.CFixedCF(SP.ones((self.P, self.P))))
            cov.addCovariance(limix.CFixedCF(SP.eye(self.P)))
            diag = SP.concatenate([SP.zeros(1), SP.ones(1)])
        elif covar_type == 'block_diag':
            cov.addCovariance(limix.CFixedCF(SP.ones((self.P, self.P))))
            cov.addCovariance(limix.CDiagonalCF(self.P))
            diag = SP.concatenate([SP.zeros(1), SP.ones(self.P)])
        else:
            assert True == False, 'CVarianceDecomposition:: covar_type not valid'

        if offset > 0:
            _cov = limix.CFixedCF(SP.eye(self.P))
            _cov.setParams(SP.array([SP.sqrt(offset)]))
            _cov.setParamMask(SP.zeros(1))
            cov.addCovariance(_cov)
        self.offset.append(offset)

        self.covar_type.append(covar_type)
        self.diag.append(diag)

        self.vd.addTerm(cov, K)
        if Ks != None: self.setKstar(self.n_terms, Ks)
        self.n_terms += 1

        self.gp = None
        self.init = False
        self.fast = False
        self.optimum = None

        self.cache['Sigma'] = None
        self.cache['Hessian'] = None
        self.cache['Lparams'] = None
        self.cache['paramsST'] = None