-#' @title dateIndexToInteger
+#' dateIndexToInteger
#'
-#' @description Transform a (potential) date index into an integer (relative to data)
+#' Transform a (potential) date index into an integer (relative to data)
#'
#' @param index Date (or integer) index
#' @param data Object of class \code{Data}
#' @export
dateIndexToInteger = function(index, data)
{
- index = index[1]
+ #works on integers too: trust input
if (is.numeric(index))
index = as.integer(index)
if (is.integer(index))
return (index)
+
if (inherits(index, "Date") || is.character(index))
{
- tryCatch(dt <- as.POSIXct(index), error=function(e) stop("Unrecognized index format"))
+ tryCatch(indexAsDate <- as.Date(index),
+ error=function(e) stop("Unrecognized index format"))
#TODO: tz arg to difftime ?
- integerIndex <- round( (as.numeric( difftime(dt, data$getTime(1)) ))[1] ) + 1
- if (integerIndex > 0 && integerIndex <= data$getSize())
- {
- #WARNING: if series start at date >0h, result must be shifted
- date1 = as.POSIXlt(data$getTime(1)[1])
- date2 = as.POSIXlt(data$getTime(2)[1])
- shift = (date1$year==date2$year && date1$mon==date2$mon && date1$mday==date2$mday)
- return (integerIndex + ifelse(shift,1,0))
- }
+ integerIndex <- round( as.numeric(
+ difftime(indexAsDate, as.Date(data$getTime(1)[1])) ) ) + 1
+ if (integerIndex >= 1 && integerIndex <= data$getSize())
+ return (integerIndex)
stop("Date outside data range")
}
stop("Unrecognized index format")
}
-#' @title integerIndexToDate
+#' integerIndexToDate
#'
-#' @description Transform an integer index to date index (relative to data)
+#' Transform an integer index to date index (relative to data)
#'
#' @param index Date (or integer) index
#' @param data Object of class \code{Data}
#' @export
integerIndexToDate = function(index, data)
{
+ #works on dates too: trust input
+ if (is.character(index))
+ index = as.Date(index)
+ if (is(index,"Date"))
+ return (index)
+
index = index[1]
if (is.numeric(index))
index = as.integer(index)
if (!is.integer(index))
- stop("'index' should be an integer")
+ stop("'index' should be a date or integer")
as.Date( data$getTime(index)[1] )
}
-#' @title getSimilarDaysIndices
+#' getSimilarDaysIndices
#'
-#' @description Find similar days indices in the past
+#' Find similar days indices in the past.
#'
#' @param index Day index (numeric or date)
+#' @param data Reference dataset, object output of \code{getData}
#' @param limit Maximum number of indices to return
-#' @param same_seaon Should the indices correspond to day in same season?
+#' @param same_season Should the indices correspond to day in same season?
+#' @param days_in Optional set to intersect with results (NULL to discard)
#'
#' @export
-getSimilarDaysIndices = function(index, limit, same_season)
+getSimilarDaysIndices = function(index, data, limit, same_season, days_in=NULL)
{
- index = dateIndexToInteger(index)
+ index = dateIndexToInteger(index, data)
- #TODO: mardi similaire à lundi mercredi jeudi aussi ...etc
- if (!same_season)
- {
- #take all similar days in recent past
- nb_days = min( (index-1) %/% 7, limit)
- return ( rep(index,nb_days) - 7*seq_len(nb_days) )
- }
-
- #Look for similar days in similar season (+/- 30 days)
+ # Look for similar days (optionally in same season)
+ i = index - 1
days = c()
- i = index
+ dt_ref = as.POSIXlt(data$getTime(index)[1]) #first date-time of current day
+ day_ref = dt_ref$wday #1=monday, ..., 6=saturday, 0=sunday
+ month_ref = as.POSIXlt(data$getTime(index)[1])$mon+1 #month in 1...12
while (i >= 1 && length(days) < limit)
{
- if (i < index)
+ dt = as.POSIXlt(data$getTime(i)[1])
+ if ((is.null(days_in) || i %in% days_in) && .isSameDay(dt$wday, day_ref))
{
- days = c(days, i)
- #look in the "future of the past"
- for (j in 1:4)
- days = c(days, i+7*j)
+ if (!same_season || .isSameSeason(dt$mon+1, month_ref))
+ days = c(days, i)
}
- #...and in the "past of the past"
- for (j in 1:4)
- {
- if (i - 7*j >= 1)
- days = c(days, i-7*j)
- }
- # TODO: exact computation instead of -364
- # 364 = closest multiple of 7 to 365 - drift along the years... but not so many years so OK
- i = i - 364
+ i = i - 1
}
+ return ( days )
+}
- return ( days[1:min(limit,length(days))] )
+# isSameSeason
+#
+# Check if two months fall in the same "season" (defined by estimated pollution rate)
+#
+# @param month month index to test
+# @param month_ref month to compare to
+#
+.isSameSeason = function(month, month_ref)
+{
+ if (month_ref %in% c(11,12,1,2)) #~= mid-polluted
+ return (month %in% c(11,12,1,2))
+ if (month_ref %in% c(3,4,9,10)) #~= high-polluted
+ return (month %in% c(3,4,9,10))
+ return (month %in% c(5,6,7,8)) #~= non polluted
+}
+
+# isSameDay
+#
+# Monday=Tuesday=Wednesday=Thursday ; Friday, Saturday, Sunday: specials
+#
+# @param day day index to test
+# @param day_ref day index to compare to
+#
+.isSameDay = function(day, day_ref)
+{
+ if (day_ref == 0)
+ return (day==0)
+ if (day_ref <= 4)
+ return (day <= 4)
+ return (day == day_ref)
+}
+
+#' getNoNA2
+#'
+#' Get indices in data of no-NA series followed by no-NA, within [first,last] range.
+#'
+#' @param data Object of class Data
+#' @param first First index (included)
+#' @param last Last index (included)
+#'
+#' @export
+getNoNA2 = function(data, first, last)
+{
+ (first:last)[ sapply(first:last, function(i)
+ !any( is.na(data$getCenteredSerie(i)) | is.na(data$getCenteredSerie(i+1)) )
+ ) ]
}