tests/testthat/test-trip.R

In spbabel: Convert Spatial Data Using Tidy Tables

testthat::skip_if_not(requireNamespace("trip"))

library(trip)
library(testthat)
context("trip")

#source("inst/examples/faketrip.r")
## Fake some data
faketrip <- function() {
  ## Brownian motion tethered at each end
  brownian.bridge <- function(n, r) {
    x <- cumsum(rnorm(n, 0, 1))
    x <- x - (x[1] + seq(0, 1, length=n) * (x[n] - x[1]))
    r * x
  }

  ## Number of days and number of obs
  days <- 50
  n <- 200

  ## Make separation between obs gamma distributed
  x <- rgamma(n, 3)
  x <- cumsum(x)
  x <- x/x[n]

  ## Track is lissajous + brownian bridge
  b.scale <- 0.6
  r.scale <- sample(c(0.1, 2, 10.2), n, replace=TRUE,
                    prob=c(0.8, 0.18, 0.02))
  set.seed(44)

  tms <- ISOdate(2001, 1, 1) + trunc(days * 24 * 60 * 60 *x)
  lon <- 120 + 20 * sin(2 * pi * x) +
    brownian.bridge(n, b.scale) + rnorm(n, 0, r.scale)
  lat <- -40 + 10 *(sin(3 * 2 * pi * x) + cos(2 * pi * x) - 1) +
    brownian.bridge(n, b.scale) + rnorm(n, 0, r.scale)

  tms2 <- tms[1:125] + 24 * 3600 * 3
  lon2 <- lat[1:125] + 90
  lat2 <- lon[1:125]-90

  tr <- new("trip",
            SpatialPointsDataFrame(rbind(cbind(lon, lat),cbind(lon2, lat2)),
                                   data.frame(gmt=c(tms, tms2), id=rep(c("lbb", "lca"), c(length(tms), length(tms2))))),
            TimeOrderedRecords(c("gmt", "id")))

  tr
}