# start "2017-10-28 00:00:00"
# end "2017-10-28 23:59:00"
# unit A character string, containing one of "sec", "min", "hour", "day", "DSTday", "week", "month", "quarter" or "year"
interval_matrix <- function(df,interv,start,end,unit){
	interv <- enquo(interv)

	time_cols <- seq.POSIXt(as_datetime(ymd_hms(start)),
							as_datetime(ymd_hms(end)),
							by="min")

  	time_str <- function(x){
  		x %>% lubridate::year() %>% as.character() %>% str_pad(2,side="left",pad="0") -> yy
  		x %>% lubridate::month() %>% as.character() %>% str_pad(2,side="left",pad="0") -> mo
  		x %>% lubridate::day() %>% as.character() %>% str_pad(2,side="left",pad="0") -> dd
  		x %>% lubridate::hour() %>% as.character() %>% str_pad(2,side="left",pad="0") -> hh
  		x %>% lubridate::minute() %>% as.character() %>% str_pad(2,side="left",pad="0") -> mm
  		x %>% lubridate::second() %>% as.character() %>% str_pad(2,side="left",pad="0") -> ss
  		paste0(yy,"_",mo,"_",dd,"_",hh,"_",mm,"_",ss)
	}

  	ltc <- length(time_cols)
  	for(i in 1:ltc){
  		p <- time_str(time_cols[i])
  		p <- paste0("time_",p)
  		df[[p]] <- time_cols[i] %within% df[[interval]] # UNDER CONSTRUCTION - NEED TO TURN QUOSURE INTO STRING FOR THIS TO WORK
	}





}