R/srcLineagePulse_decompressParameters.R

In LineagePulse: Differential expression analysis and model fitting for single-cell RNA-seq data

#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
#++++++++    Decompress parameters: Compute parameter values from model  +++++#
#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#

#' Compute mean parameter estimates from mean parameter model for a gene
#' 
#' Takes the model type and computes one mean parameter for each cell for one
#' gene.
#' 
#' @seealso Called by \code{fitZINB}.
#'
#' @param vecMuModel (numerical vector number of model parameters)
#' Parameters of mean model for given gene.
#' @param lsvecBatchModel (list) 
#' List of vectors of batch correction models for mean parameter.
#' @param lsMuModelGlobal (list) 
#' Object containing meta-data of gene-wise mean parameter models.
#' @param vecInterval (integer vector length target cells) [Default NULL]
#' Positions of cells in ordering, for which parameters are to be 
#' computed. Default all cells.
#' 
#' @return vecMu (numerical vector number of cells)
#' Mean parameter estimates for given gene given the mean model.
#' 
#' @author David Sebastian Fischer
decompressMeansByGene <- function(
    vecMuModel,
    lsvecBatchModel=NULL,
    lsMuModelGlobal,
    vecInterval=NULL ){
    
    if(lsMuModelGlobal$strMuModel=="constant"){
        if(!is.null(vecInterval)){ 
            vecMu <- rep(vecMuModel, length(vecInterval))
        } else { 
            vecMu <- rep(vecMuModel, lsMuModelGlobal$scaNumCells) 
        }
    } else if(lsMuModelGlobal$strMuModel=="impulse"){
        if(!is.null(vecInterval)){
            vecMu <- evalImpulseModel_comp(
                vecImpulseParam=vecMuModel, 
                vecTimepoints=lsMuModelGlobal$vecContinuousCovar[vecInterval])
        } else { 
            vecMu <- evalImpulseModel_comp(
                vecImpulseParam=vecMuModel, 
                vecTimepoints=lsMuModelGlobal$vecContinuousCovar) 
        }
    } else if(lsMuModelGlobal$strMuModel=="splines"){
        if(!is.null(vecInterval)){
            vecMu <- exp(as.vector(lsMuModelGlobal$matSplineBasis[
                vecInterval,,drop=FALSE] %*% vecMuModel))
        } else { 
            vecMu <- exp(as.vector(
                lsMuModelGlobal$matSplineBasis %*% vecMuModel))
        }
    } else if(lsMuModelGlobal$strMuModel=="groups"){
        if(!is.null(vecInterval)){ 
            vecMu <- vecMuModel[lsMuModelGlobal$vecidxGroups[vecInterval]]
        } else { 
            vecMu <- vecMuModel[lsMuModelGlobal$vecidxGroups]
        }
    }  else if(lsMuModelGlobal$strMuModel=="MM"){
        # Expect mean of ONE MIXTURE component! vecMuModel is scalar
        if(!is.null(vecInterval)){ 
            vecMu <- rep(vecMuModel, length(vecInterval))
        } else { 
            vecMu <- rep(vecMuModel, lsMuModelGlobal$scaNumCells)
        }
    } else {
        stop("ERROR decompressMeans(): lsMuModelGlobal$strMuModel=", 
             lsMuModelGlobal$strMuModel, " not recognised.")
    }
    # Scale by batch factors
    if(!is.null(lsMuModelGlobal$lsvecidxBatchAssign)){
        for(conf in seq_len(lsMuModelGlobal$scaNConfounders)){
            if(!is.null(vecInterval)){
                vecMu <- vecMu*(lsvecBatchModel[[conf]][
                    (lsMuModelGlobal$lsvecidxBatchAssign[[conf]])[
                        vecInterval]])
            } else { 
                vecMu <- vecMu*(lsvecBatchModel[[conf]][
                    lsMuModelGlobal$lsvecidxBatchAssign[[conf]]])
            }
        }
    }
    
    return(vecMu)
}

#' Compute mean parameter estimate matrix from mean parameter model 
#' for a gene (strMuModel == "MM")
#'
#' @param vecMuModel (numerical vector number of model parameters)
#' Parameters of mean model for given gene (means by mixture).
#' @param lsvecBatchModel (list) [Defaul NULL] 
#' List of vectors of batch correction models for mean parameter.
#' @param lsMuModelGlobal (list) 
#' Object containing meta-data of gene-wise mean parameter models.
#' @param vecInterval (integer vector length target cells) [Default NULL]
#' Positions of cells in ordering, for which parameters are to be 
#' computed. Default all cells.
#' 
#' @return matMu (matrix number of cells x number of mixtures)
#' Mean parameter estimates for given gene given the mean model.
#' 
#' @author David Sebastian Fischer
decompressMuByGeneMM <- function(
    vecMuModel,
    lsvecBatchModel=NULL,
    lsMuModelGlobal,
    vecInterval=NULL ){
    
    # Scaling by batch factors is constant across mixtures
    vecBatchScale <- matrix(1, nrow = lsMuModelGlobal$scaNumCells, ncol = 1)
    if(!is.null(lsMuModelGlobal$lsvecidxBatchAssign)){
        for(conf in seq_len(lsMuModelGlobal$scaNConfounders)){
            if(!is.null(vecInterval)){
                vecBatchScale <- vecBatchScale*(lsvecBatchModel[[conf]][
                    (lsMuModelGlobal$lsvecidxBatchAssign[[conf]])[
                        vecInterval]])
            } else { 
                vecBatchScale <- vecBatchScale*(lsvecBatchModel[[conf]][
                    lsMuModelGlobal$lsvecidxBatchAssign[[conf]]])
            }
        }
    }
    
    matMu <- vecBatchScale %*% vecMuModel
        
    return(matMu)
}

#' Compute dispersion parameter estimates from mean parameter model for a gene
#' 
#' Takes the model type and computes one dispersion parameter 
#' for each cell for one gene.
#' 
#' @seealso Called by \code{fitZINB}.
#' 
#' @param vecDispModel (numerical vector number of model parameters)
#' Parameters of dispersion model for given gene.
#' @param lsvecBatchModel (list) [Defaul NULL] 
#' List of vectors of batch correction models for dispersion parameter.
#' @param lsDispModelGlobal (list) 
#' Object containing meta-data of gene-wise dispersion parameter models.
#' @param vecInterval (integer vector length target cells) [Default NULL]
#' Positions of cells in ordering, for which parameters are to be 
#' computed. Default all cells.
#' 
#' @return vecDisp (numerical vector number of cells)
#' Dispersion parameter estimates for given gene 
#' (one per cell for given gene).
#' 
#' @author David Sebastian Fischer
decompressDispByGene <- function(
    vecDispModel,
    lsvecBatchModel=NULL,
    lsDispModelGlobal,
    vecInterval=NULL ){
    
    if(lsDispModelGlobal$strDispModel=="constant"){
        if(!is.null(vecInterval)) { 
            vecDisp <- rep(vecDispModel, length(vecInterval))
        } else { 
            vecDisp <- rep(vecDispModel, lsDispModelGlobal$scaNumCells)
        }
    } else if(lsDispModelGlobal$strDispModel=="splines"){
        if(!is.null(vecInterval)){
            vecDisp <- exp(as.vector(lsDispModelGlobal$matSplineBasis[
                vecInterval,,drop=FALSE] %*% vecDispModel))
        } else { 
            vecDisp <- exp(as.vector(lsDispModelGlobal$matSplineBasis %*% 
                                         vecDispModel))
        }
    } else if(lsDispModelGlobal$strDispModel=="groups"){
        if(!is.null(vecInterval)){ 
            vecDisp <- vecDispModel[
                lsDispModelGlobal$vecidxGroups[vecInterval]]
        } else { 
            vecDisp <- vecDispModel[lsDispModelGlobal$vecidxGroups]
        }
    } else if(lsDispModelGlobal$strDispModel=="MM"){
        # Expect mean of ONE MIXTURE component! vecDispModel is scalar
        if(!is.null(vecInterval)){ 
            vecDisp <- rep(vecDispModel, length(vecInterval))
        } else { 
            vecDisp <- rep(vecDispModel, lsDispModelGlobal$scaNumCells)
        }
    } else {
        stop("ERROR decompressDispersions():",
             " lsDispModelGlobal$strDispModel=", 
             lsDispModelGlobal$strDispModel, 
             " not recognised.")
    }
    
    # Scale by batch factors
    if(!is.null(lsDispModelGlobal$lsvecidxBatchAssign)){
        for(conf in seq_len(lsDispModelGlobal$scaNConfounders)){
            if(!is.null(vecInterval)){
                vecDisp <- vecDisp*(lsvecBatchModel[[conf]][
                    (lsDispModelGlobal$lsvecidxBatchAssign[[conf]])[
                        vecInterval]])
            } else { 
                vecDisp <- vecDisp*(lsvecBatchModel[[conf]][
                    lsDispModelGlobal$lsvecidxBatchAssign[[conf]]])
            }
        }
    }
    
    return(vecDisp)
}

#' Compute mean parameter estimate matrix from mean parameter model 
#' for a gene (strDispModel == "MM")
#' 
#' @param vecDispModel (numerical vector number of model parameters)
#' Parameters of dispersion model for given gene.
#' @param lsvecBatchModel (list) [Defaul NULL] 
#' List of vectors of batch correction models for dispersion parameter.
#' @param lsDispModelGlobal (list) 
#' Object containing meta-data of gene-wise dispersion parameter models.
#' @param vecInterval (integer vector length target cells) [Default NULL]
#' Positions of cells in ordering, for which parameters are to be 
#' computed. Default all cells.
#' 
#' @return matDisp (matrix number of cells x number of mixtures)
#' Dispersion parameter estimates for given gene given the mean model.
#' 
#' @author David Sebastian Fischer
decompressDispByGeneMM <- function(
    vecDispModel,
    lsvecBatchModel=NULL,
    lsDispModelGlobal,
    vecInterval=NULL ){
    
    # Scaling by batch factors is constant across mixtures
    vecBatchScale <- matrix(1, nrow = lsDispModelGlobal$scaNumCells, ncol = 1)
    if(!is.null(lsDispModelGlobal$lsvecidxBatchAssign)){
        for(conf in seq_len(lsDispModelGlobal$scaNConfounders)){
            if(!is.null(vecInterval)){
                vecBatchScale <- vecBatchScale*(lsvecBatchModel[[conf]][
                    (lsDispModelGlobal$lsvecidxBatchAssign[[conf]])[
                        vecInterval]])
            } else { 
                vecBatchScale <- vecBatchScale*(lsvecBatchModel[[conf]][
                    lsDispModelGlobal$lsvecidxBatchAssign[[conf]]])
            }
        }
    }
    
    if(lsDispModel$lsDispModelGlobal$strDispModel=="constant"){
        matDispParam <- matrix(vecBatchScale*vecDispModel, 
                               nrow = length(vecBatchScale), 
                               ncol = lsDispModelGlobal$scaNMix, 
                               byrow = FALSE)
    } else if(lsDispModel$lsDispModelGlobal$strDispModel=="MM"){
        matDisp <- vecBatchScale %*% vecDispModel
    } else {
        stop("ERROR decompressDispByGeneMM():",
             " lsDispModelGlobal$strDispModel=", 
             lsDispModelGlobal$strDispModel, 
             " not recognised.")
    }
        
    return(matDisp)
}

#' Compute dropout rate parameter estimates from dropout rate model for a gene
#' 
#' Compute dropout rate parameter estimates 
#' from dropout rate model for a gene.
#' 
#' @seealso Called by \code{fitZINB}.
#'
#' @param matDropModel (numerical matrix cell x number of model parameters)
#' {offset parameter, log(mu) parameter, parameters belonging to
#' constant predictors}
#' Parameters of dropout rate model for all cells.
#' @param vecMu (numerical vector number of genes)
#' Mean parameter estimates of all cells for given gene.
#' @param vecPiConstPredictors (numerical vector number of 
#' constant model predictors) Other model predictors than offset
#' and the dynamically changing mean parameter. Examples are GC-
#' content and other gene-specific properties. This would be the 
#' global parameters as listed in the other decompression
#' function. Here those are not a list as there is only one object.
#' @param lsDropModelGlobal (list) 
#' Object containing meta-data of cell-wise dropout parameter models.
#' 
#' @return vecPi (numerical vector number of cells)
#' Dispersion parameter estimates for given gene 
#' (one per cell for given gene).
#' 
#' @author David Sebastian Fischer
decompressDropoutRateByGene <- function(
    matDropModel,
    vecMu=NULL,
    vecPiConstPredictors=NULL,
    lsDropModelGlobal ){
    
    if(lsDropModelGlobal$strDropModel=="logistic"){
        vecPi <- sapply(seq_len(lsDropModelGlobal$scaNumCells), function(j){
            evalDropoutModel_comp(vecPiModel=matDropModel[j,], 
                                  vecPiPredictors=c(1, vecPiConstPredictors))
        })
    } else if(lsDropModelGlobal$strDropModel=="logistic_ofMu"){
        vecPi <- sapply(seq_len(lsDropModelGlobal$scaNumCells), function(j){
            evalDropoutModel_comp(vecPiModel=matDropModel[j,], 
                                  vecPiPredictors=c(1, log(vecMu[j]), 
                                                    vecPiConstPredictors))
        })
    } else {
        stop("ERROR IN decompressDropoutRateByGene: ",
             "lsDropModelGlobal$strDropModel=",
             lsDropModelGlobal$strDropModel,
             " not recognised.")
    }
    
    return(vecPi)
}

#' Compute dropout rate parameter estimates from dropout rate model for a cell
#' 
#' Compute dropout rate parameter estimates 
#' from dropout rate model for a cell.
#' 
#' @seealso Called by \code{fitZINB}.
#'
#' @param vecDropModel (numerical vector number of model parameters)
#' {offset parameter, log(mu) paramter, parameters belonging to
#' constant predictors}
#' Parameters of dropout rate model for given cell.
#' @param vecMu (numerical vector number of genes)
#' Mean parameter estimates of all genes for given cell.
#' @param matPiConstPredictors (numerical matrix genes x number of 
#' constant model predictors) Other model predictors than offset
#' and the dynamically changing mean parameter. Examples are GC-
#' content and other gene-specific properties. This would be the 
#' global parameters as listed in the other decompression
#' function. Here those are not a list as there is only one object.
#' @param lsDropModelGlobal (list) 
#' Object containing meta-data of cell-wise dropout parameter models.
#' 
#' @return vecPi (numerical vector number of cells)
#' Dispersion parameter estimates for given gene 
#' (one per cell for given gene).
#' 
#' @author David Sebastian Fischer
decompressDropoutRateByCell <- function(
    vecDropModel,
    vecMu=NULL,
    matPiConstPredictors=NULL,
    lsDropModelGlobal){
    
    if(lsDropModelGlobal$strDropModel=="logistic"){
        vecPi <- sapply(seq_len(lsDropModelGlobal$scaNumGenes), function(i){
            evalDropoutModel_comp(vecPiModel = vecDropModel, 
                                  vecPiPredictors = 
                                      c(1, matPiConstPredictors[i,]))
        })
    } else if(lsDropModelGlobal$strDropModel=="logistic_ofMu"){
        vecPi <- sapply(seq_len(lsDropModelGlobal$scaNumGenes), function(i){
            evalDropoutModel_comp(vecPiModel=vecDropModel, 
                                  vecPiPredictors=c(1, log(vecMu[i]), 
                                                    matPiConstPredictors[i,]))
        })
    } else {
        stop("ERROR IN decompressDropoutRateByCell: ",
             "lsDropModelGlobal$strDropModel=",
             lsDropModelGlobal$strDropModel,
             " not recognised.")
    }
    
    return(vecPi)
}