Get Events by Evaluation of a State Variable

Get Events by Evaluation of a State Variable

eventsByState(timestamps, states, eventSeparationTime, signalWidth,
  in.state = 1, out.state = 0)

Arguments

timestamps

vector of timestamps (POSIXct)

states

vector of state values in which each element corresponds to one timestamp in timstamps. If the state is the value given in in.state) the corresponding times are considered to be lying within an event. If the state is the value given in out.state) the corresponding times are considered to be lying out of an event. For values that are neither of the values given in in.state and out.state, respectively, the corresponding timestamps are considered to either belong to an event or not, depending on the previous clear state ("in" or "out") in the sequence of states.

eventSeparationTime

same meaning as in hsEvents

signalWidth

see description in hsEvents

in.state

value in states indicating the state "in event". Default: 1

out.state

value in states indicating the state "out of event". Default: 0

Value

event characteristics (begin, end, duration, ...) in a data frame, as returned by hsEvents

Examples

  
# Generate random timestamps
starttime <- as.POSIXct("2015-03-12 10:51")
    
n <- 100
timestamps <- seq(starttime, by = 60, length.out = n)
values <- rnorm(n)
  
# Give values above 1 the state "in" and values below -1 the state "out"
states <- rep("", times = n)
states[values > 1] <- "in"
states[values < -1] <- "out"
  
# Generate the events
events <- eventsByState(
  timestamps, states, eventSeparationTime = 5 * 60, in.state = "in", 
  out.state = "out", signalWidth = 60
)
  
# Prepare a vector of colours
col <- rep("black", length(states))
col[states == "in"] <- "green"
col[states == "out"] <- "red"
  
# Plot the values, the threshold lines and a legend
graphics::plot(timestamps, values, type = "l", ylim = c(-5, 5))
points(timestamps, values, col = col)
  
graphics::abline(h = c(1, -1), lty = 2)
  
legend(
  "topright", bty = "n", legend = c("in", "out"), col = c("green", "red"), 
   pch = 1, bg = "white", horiz = TRUE
)
  
# Plot the event borders
ganttPlotEvents(events, add = TRUE, y1 = -5, y2 = 4)