test.r

for (i in levels(scot_battles_centroid_dates$century)) { # the levels are "1200s" to "1900s"
  battle_road_dist <- gDistance(scot_battles_centroid_dates[scot_battles_centroid_dates$century == i,], sp, byid = TRUE) # euclidean distance from battle point to road. 
  battle_road_dist_vect <- data.frame(as.vector(battle_road_dist)) # creates df of the distances
  dist_test <- rbind(battle_road_dist_vect) # adds to a df to create one df with all of the distances
}