flightpathr

commit 5bec21e8c874aab58f1737424f6888861ae77279
parent da7705cec5650b6a09891608121f9fb8f9c2ce01
Author: eamoncaddigan <eamon.caddigan@gmail.com>
Date:   Wed, 27 Apr 2016 12:02:44 -0400

Untested code...

Diffstat:
A
R/identifyManeuvers.R
 | 
45
+++++++++++++++++++++++++++++++++++++++++++++

1 file changed, 45 insertions(+), 0 deletions(-)
diff --git a/R/identifyManeuvers.R b/R/identifyManeuvers.R
@@ -0,0 +1,45 @@
+#' Identify the timepoints in a trajectory that correspond to a change in
+#' commanded heading.
+#'
+#' @param trajectory A matrix or SpatialPoints object indicating the trajectory
+#'   of an aircraft.
+#' @param hiThresh A heading change (in degrees); any time point associated with
+#'   a change in heading greater than this value will definitely be labeled a
+#'   turn.
+#'
+#' @return A logical vector indicating whether each timepoint can be considered
+#'   a turn.
+#'
+#' @export
+identifyHeadingChanges <- function(trajectory, hiThresh) {
+  bearings <- coordsToBearing(trajectory)
+
+  bearings[length(bearings)] <- bearings[length(bearings)-1]
+  bearingChanges <- c(diff(bearings), 0)
+
+  isBearingChange <- abs(bearingChanges) < hiThresh
+
+  return(isBearingChange)
+}
+
+#' Identify the timepoints in a trajectory that correspond to a change in
+#' altitude.
+#'
+#' @param trajectory A matrix or SpatialPoints object indicating the trajectory
+#'   of an aircraft.
+#' @param hiThresh An altitude change (in feet); any time point associated with
+#'   a change in altitude greater than this value will definitely be labeled a
+#'   climb or descent.
+#'
+#' @return A logical vector indicating whether each timepoint can be considered
+#'   a climb or descent.
+#'
+#' @export
+identifyAltitudeChanges <- function(trajectory, hiThresh) {
+  trajectoryCoords <- get3dCoords(trajectory)
+  altitudeChanges <- c(diff(trajectoryCoords[, 3]), 0)
+
+  isAltitudeChange <- abs(altitudeChanges) < hiThresh
+
+  return(isAltitudeChange)
+}