R/import-2-subcol_f.R

In junyitt/tfunction: tfunction for Trading Purposes

#' subcol_f
#'
#' Subset useful columns from raw df 
#' Imports: NA
#' Return df
#' @param raw_df
#' @param subcol_df
#' @param importance
#' @keywords subset useful columns
#' @export
#' @examples
#' subcol_f(raw_df, subcol_df, importance = 1)
subcol_f <- function(raw_df, subcol_df, importance = 1){
      
      if(is.null(raw_df)){
            return(NULL)
      }
      #better to attach subcol_df to the library/package itself
      u1 <- subcol_df[,"importance"] >= importance
      selected_columns <- subcol_df[u1,"colname"]
      all_columns <- colnames(raw_df)
      
      u2 <- all_columns %in% selected_columns
      selected_columns_2 <- all_columns[u2]
            
      sub_df <- raw_df[, selected_columns_2]
                    
      return(sub_df)
}