Running examples in 'amt-Ex.R' failed
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> ### Name: steps
> ### Title: Functions to create and work with steps
> ### Aliases: steps direction_abs direction_abs.track_xy direction_rel
> ###   direction_rel.track_xy step_lengths step_lengths.track_xy
> ###   steps_by_burst steps_by_burst.track_xyt steps steps.track_xy
> ###   steps.track_xyt
> 
> ### ** Examples
> 
> 
> 
> # Absolute directions
> 
> xy <- data_frame(
+   x = c(1, 4, 8, 8, 12, 8, 0, 0, 4, 2),
+   y = c(0, 0, 0, 8, 12, 12, 12, 8, 4, 2))
> trk <- mk_track(xy, x, y)
.t missing, creating `track_xy`.
> 
> # append last
> direction_abs(trk, append_last = TRUE)
 [1]    0    0   90   45  180  180  -90  -45 -135   NA
> direction_abs(trk, append_last = FALSE)
[1]    0    0   90   45  180  180  -90  -45 -135
> 
> # degrees
> direction_abs(trk, degrees = FALSE)
 [1]  0.0000000  0.0000000  1.5707963  0.7853982  3.1415927  3.1415927
 [7] -1.5707963 -0.7853982 -2.3561945         NA
> direction_abs(trk, degrees = TRUE)
 [1]    0    0   90   45  180  180  -90  -45 -135   NA
> 
> # full circle or not
> direction_abs(trk, degrees = TRUE, full_circle = TRUE)
 [1]   0   0  90  45 180 180 270 315 225  NA
> direction_abs(trk, degrees = TRUE, full_circle = FALSE)
 [1]    0    0   90   45  180  180  -90  -45 -135   NA
> 
> # direction of 0
> direction_abs(trk, full_circle = TRUE, zero_dir = "N")
 [1] 270 270   0 315  90  90 180 225 135  NA
> direction_abs(trk, full_circle = TRUE, zero_dir = "E")
 [1]   0   0  90  45 180 180 270 315 225  NA
> direction_abs(trk, full_circle = TRUE, zero_dir = "S")
 [1]  90  90 180 135 270 270   0  45 315  NA
> direction_abs(trk, full_circle = TRUE, zero_dir = "W")
 [1] 180 180 270 225   0   0  90 135  45  NA
> 
> # clockwise or not
> direction_abs(trk, full_circle = TRUE, zero_dir = "N", clockwise = FALSE)
 [1] 270 270   0 315  90  90 180 225 135  NA
> direction_abs(trk, full_circle = TRUE, zero_dir = "N", clockwise = TRUE)
 [1]  90  90   0  45 270 270 180 135 225  NA
> 
> # Bearing (i.e. azimuth): only for lon/lat
> direction_abs(trk, full_circle = FALSE, zero_dir = "N", lonlat = FALSE, clockwise = TRUE)
 [1]   90   90    0   45  -90  -90  180  135 -135   NA
> direction_abs(trk, full_circle = FALSE, zero_dir = "N", lonlat = TRUE, clockwise = TRUE)
 [1]   90.00000   90.00000    0.00000   44.41780  -89.58401  -89.16705
 [7]  180.00000  134.74039 -134.79070         NA
> 
> # How do results compare to other packages
> # adehabitatLT
> df <- adehabitatLT::as.ltraj(data.frame(x = xy$x, y = xy$y), typeII = FALSE, id = 1)
> df[[1]]$abs.angle
 [1]  0.0000000  0.0000000  1.5707963  0.7853982  3.1415927  3.1415927
 [7] -1.5707963 -0.7853982 -2.3561945         NA
> amt::direction_abs(trk, degrees = FALSE, full_circle = FALSE)
 [1]  0.0000000  0.0000000  1.5707963  0.7853982  3.1415927  3.1415927
 [7] -1.5707963 -0.7853982 -2.3561945         NA
> 
> # bcpa
> df <- bcpa::MakeTrack(xy$x, xy$y, lubridate::now() +  lubridate::hours(1:10))
> bcpa::GetVT(df)$Phi
[1]  0.0000000  1.5707963  0.7853982  3.1415927  3.1415927 -1.5707963 -0.7853982
[8] -2.3561945
> direction_abs(trk, degrees = FALSE, full_circle = FALSE, append_last = FALSE)
[1]  0.0000000  0.0000000  1.5707963  0.7853982  3.1415927  3.1415927 -1.5707963
[8] -0.7853982 -2.3561945
> 
> # move
> m <- move::move(xy$x, xy$y, lubridate::now() + lubridate::hours(1:10),
+  proj = sp::CRS("+init=epsg:4326"))
> move::angle(m)
[1]   90.00000   90.00000    0.00000   44.41780  -89.58401  -89.16705 -180.00000
[8]  134.74039 -134.79070
> direction_abs(trk, degrees = TRUE, full_circle = FALSE, zero_dir = "N",
+   clockwise = TRUE, append_na = FALSE, lonlat = TRUE)
 [1]   90.00000   90.00000    0.00000   44.41780  -89.58401  -89.16705
 [7]  180.00000  134.74039 -134.79070         NA
> 
> # trajectories
> t1 <- trajectories::Track(
+   spacetime::STIDF(sp::SpatialPoints(cbind(xy$x, xy$y)),
+   lubridate::now() + lubridate::hours(1:10), data = data.frame(1:10)))
> 
> t1[["direction"]]
[1]  90  90   0  45 270 270 180 135 225
> direction_abs(trk, degrees = TRUE, full_circle = TRUE, zero_dir = "N",
+   clockwise = TRUE, append_last = FALSE)
[1]  90  90   0  45 270 270 180 135 225
> 
> # moveHMM (only rel. ta)
> df <- data.frame(ID = 1, x = xy$x, y = xy$y)
> moveHMM::prepData(df, type = "UTM")
   ID     step      angle  x  y
1   1 3.000000         NA  1  0
2   1 4.000000  0.0000000  4  0
3   1 8.000000  1.5707963  8  0
4   1 5.656854 -0.7853982  8  8
5   1 4.000000  2.3561945 12 12
6   1 8.000000  0.0000000  8 12
7   1 4.000000  1.5707963  0 12
8   1 5.656854  0.7853982  0  8
9   1 2.828427 -1.5707963  4  4
10  1       NA         NA  2  2
> # How do results compare to other packages
> xy <- data_frame(
+   x = c(1, 4, 8, 8, 12, 8, 0, 0, 4, 2),
+   y = c(0, 0, 0, 8, 12, 12, 12, 8, 4, 2))
> trk <- mk_track(xy, x, y)
.t missing, creating `track_xy`.
> # adehabitatLT
> df <- adehabitatLT::as.ltraj(data.frame(x = xy$x, y = xy$y), typeII = FALSE, id = 1)
> df[[1]]$rel.angle
 [1]         NA  0.0000000  1.5707963 -0.7853982  2.3561945  0.0000000
 [7]  1.5707963  0.7853982 -1.5707963         NA
> amt::direction_rel(trk, degrees = FALSE, full_circle = FALSE)
 [1]         NA  0.0000000  1.5707963 -0.7853982  2.3561945  0.0000000
 [7]  1.5707963  0.7853982 -1.5707963         NA
> 
> # trajectories
> t1 <- trajectories::Track(
+   spacetime::STIDF(sp::SpatialPoints(cbind(xy$x, xy$y)),
+   lubridate::now() + lubridate::hours(1:10), data = data.frame(1:10)))
Warning in with_tz(Sys.time(), tzone) : Unrecognized time zone ''
Error in (function (dt, year, month, yday, mday, wday, hour, minute, second,  : 
  Invalid timezone of input vector: ""
Calls: <Anonymous> ... reclass_date.POSIXlt -> as.POSIXlt -> do.call -> <Anonymous> -> .Call
Execution halted