R/class.R

In HiLDA: Conducting statistical inference on comparing the mutational exposures of mutational signatures by using hierarchical latent Dirichlet allocation

#' An S4 class to represent a mutation meta information common to many data
#'   types
#'
#'  @slot type type of data format (independent, full, custom)
#'  @slot flankingBasesNum the number of flanking bases to consider (only
#'        applicable for independent and full types)
#'  @slot transcriptionDirection the flag representing whether transcription
#'        direction is considered or not
#'  @slot possibleFeatures a vector representing the numbers of possible values
#'        for each mutation feature
setClass("MetaInformation",
    representation = representation(
    "VIRTUAL",
    type = "character",
    flankingBasesNum = "integer",
    transcriptionDirection = "logical",
    possibleFeatures = "integer"
    )
)

#' An S4 class representing the mutation data
#'
#' @slot featureVectorList a list of feature vectors actually observed
#'       in the input mutation data
#' @slot sampleList a list of sample names observed in the input mutation
#'       data
#' @slot countData a matrix representing the number of mutations and
#'       samples. The (1st, 2nd, 3rd) columns are for (mutation pattern
#'       index, sample index, frequencies).
#' @slot mutationPosition a data frame containing position and mutations
#'
#' @export
setClass(
    Class = "MutationFeatureData",
    contains = "MetaInformation",
    representation = representation(
    featureVectorList = "matrix",
    sampleList = "character",
    countData = "matrix",
    mutationPosition = "data.frame"
    ),
    validity = function(object) {
    errors <- character()
    # check for the consistency about the possible feature vector.
    for (i in seq_len(length(object@possibleFeatures))) {
        if (any(!(object@featureVectorList[i] %in%
                seq_len(object@possibleFeatures[i])))) {
          errors <- c(errors,
          paste("Inconsistency in the ", i, "-th feature", sep = ""))
      }
    }
      # check for the number of mutation patterns
    if (any(!sort(unique(object@countData[1,])) %in%
            seq_len(ncol(object@featureVectorList)))) {
      errors <- c(errors,
                  "Inconsistency about the number of mutation patterns")
    }
    # check for the number of samples
    if (any(!sort(unique(object@countData[2,])) %in%
            seq_len(length(object@sampleList)))) {
      errors <- c(errors, "Inconsistency about the sample indice")
    }
    # check for the zero count
    if (any(!object@countData[3,] != 0)) {
      errors <- c(errors, "The count data should not include 0");
    }
    if (length(errors) == 0) TRUE else errors
  }
)

#' An S4 class representing the estimated parameters
#' 
#' @slot sampleList a list of sample names observed in the input mutation data
#' @slot signatureNum the number of mutation signatures specified at the time 
#'       of estimation
#' @slot isBackGround the flag showing whether the background signature data is 
#'       used or not.
#' @slot backGroundProb the background signatures
#' @slot signatureFeatureDistribution estimated parameters for mutation 
#'       signatures
#' @slot sampleSignatureDistribution estimated parameters for memberships of 
#'       mutation signatures for each sample
#' @slot loglikelihood the log-likelihood  value for the estimated parameters
#' @export
setClass(
    Class = "EstimatedParameters",
    contains = "MetaInformation",
    representation = representation(
        sampleList = "character",
        signatureNum = "integer",
        isBackGround = "logical",
        backGroundProb = "numeric",
        signatureFeatureDistribution = "array",
        sampleSignatureDistribution = "matrix",
        loglikelihood = "numeric"
    ),
    validity = function(object) {
        errors <- character()
        variantSignatureNum = object@signatureNum - 
        as.integer(object@isBackGround)
        # check for the estimated signature feature distribution
        if (any(object@signatureFeatureDistribution < 0) || 
            any(object@signatureFeatureDistribution > 1)) {
        errors <- c(errors, "The estimated signature feature distribution value 
                    should be between 0 to 1")
        }
        for (k in seq_len(variantSignatureNum)) {
            for (l in seq_len(length(object@possibleFeatures))) {
                if (abs(sum(object@signatureFeatureDistribution[k, l, 
                    seq_len(object@possibleFeatures[l])]) - 1) > 1e-10) {
            errors <- c(errors, paste("The estimated values should sum to 1 at 
            the ", k, "-th signature and the ", l, "-th feature", sep=""))
          }
        }
      }
      # check for estimated sample signature distribution
      if (any(object@sampleSignatureDistribution < 0) || 
          any(object@sampleSignatureDistribution > 1)) {
        errors <- c(errors, "The estimated signature feature distribution value 
                    should be between 0 to 1")
      }    
      if (nrow(object@sampleSignatureDistribution) != 
          length(object@sampleList)) {
        errors <- c(errors, "Inconsistency in the number of samples and the 
                    estimated sample signature distibution")
      }
      if (ncol(object@sampleSignatureDistribution) != object@signatureNum) {
        errors <- c(errors, "Inconsistency in the number of signatures and the 
                    estimated sample signature distibution")
      }
      for (n in seq_len(nrow(object@sampleSignatureDistribution))) {
        if (abs(sum(object@sampleSignatureDistribution[n, ]) - 1) > 1e-10) {
          errors <- c(errors, 
          paste("The estimated values should sum to 1 at the ", n, 
                "-th sample", sep=""))
        }
      }      
      
      if (length(errors) == 0) TRUE else errors
    }
)