R/VKT_table.R

In Iavalos/VKT: An implementation of the VKT in a region.

VKT_table <- function(unique.ID, location.ID, df.base, df.assumptions, mode, purpose, policy=NA, share= NA, Npt=NA){
  pop = subset(df.assumptions, Category == "Trip_rates"& Subcategory=="Pop" & Location.ID == location.ID)$Value *
    subset(df.base, MMU.ID==unique.ID & location.ID == location.ID)$population
  job = subset(df.assumptions, Category == "Trip_rates"& Subcategory=="Jobs"& Location.ID == location.ID)$Value *
    subset(df.base, MMU.ID==unique.ID & location.ID == location.ID)$employment
  p.t = pop+job


  vehicle = subset(df.assumptions, Category == "Mode_split"& Subcategory==mode &
                 Location.ID==location.ID & Units == "per person")$Value

  mode.trips =  p.t * vehicle
  distance = subset(df.assumptions, Category == "Travel_distance"& Subcategory==purpose &
                      Location.ID==location.ID)$Value
  
  split = subset(df.assumptions, Category == "Trip_split"& Subcategory==purpose)$Value
  

  if(is.na(policy)){
    split = split
  } else { if(mode == "Car"){split = split*(1-(subset(df.assumptions,
                                                      Category == "Scenarios"& Subcategory==policy)$Value*share)/100)}
    else{split= split*(1+(abs((subset(df.assumptions,
                                      Category == "Scenarios"& Subcategory==policy)$Value*share)/100)/Npt))}
  }

  VKT = mode.trips *distance*split
  return(VKT)
}