R/dataTransform.R

In thomaswiemann/SMLpractical:

#' Transform data from matrix of strings to data frame with factors or to model matrix
#'
#' @param x is an object
#' @return y is the output
#' @export

dataTransform <- function(dat, levels, model.Matrix = FALSE){
  # Transform from matrix of strings to data.frame with factors
  df <- as.data.frame(dat)
  df[] <- lapply(df, factor, levels = levels)

  if(model.Matrix){
    df$c <- matrix(1L, nrow=nrow(as.matrix(dat)), ncol=1)
    mat <- model.matrix(c~. , data = df)[,-1] #mat.sparse <- sparse.model.matrix(c~., data = df)
    return(mat)

  } else {
    df[] <- lapply(df, as.numeric, levels = levels)
    return(df)
  }
}