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trajr

Trajectory Analysis in R

An R package for analysing animal trajectories, which represent the movements of animals through space and time. It provides functions to easily calculate various quantitative measures of trajectories such as speed and straightness or tortuosity. It also provides a range of other trajectory operations such as resampling to fixed step lengths (rediscretization), determining turning angles and step lengths, and so on. While mainly focussed on 2-dimensional trajectories, trajr does have some functionality for analysing 3-dimensional trajectories. If you use trajr in your research, please cite McLean, D. J., & Skowron Volponi, M. A. (2018). trajr: An R package for characterisation of animal trajectories. Ethology, 124(6), 440-448. https://doi.org/10.1111/eth.12739.

trajr does not provide functionality to create trajectories; it operates on existing trajectories that are sequences of (x, y, time) coordinates. It does, however, provide some functionality to generate random or constrained trajectories for simulations or for testing of analyses.

Refer to NEWS.md for a list of changes in each version. The article trajr: An R package for characterisation of animal trajectories described trajr version 1.0.0. Please refer to NEWS.md for a brief summary of what has changed since the article was written.

Installation

$ install.packages("trajr")

Or to install the latest development version directly from Github:

$ install.packages("devtools")
$ devtools::install_github("JimMcL/trajr")

Or else, to install from Github and get the user documentation (vignette):

$ install.packages("devtools")
$ devtools::install_github("JimMcL/trajr", build_vignettes = TRUE)

Unfortunately, installing vignettes can be time-consuming.

Using trajr

The best way to start is to read our paper and the package vignette. After installation from CRAN (or from github including vignettes), the vignette can be accessed by running browseVignettes(package = "trajr"). The vignette for the CRAN version is available on CRAN at https://cran.r-project.org/web/packages/trajr/vignettes/trajr-vignette.html.

A vignette demonstrating trajectory simulation is available online at https://cran.r-project.org/web/packages/trajr/vignettes/simulations.html.

Environment

─ Session info ────────────────────────────────────────────────────────────────────────────────────────────────────────────
 setting  value
 version  R version 4.2.2 (2022-10-31 ucrt)
 os       Windows 10 x64 (build 22631)
 system   x86_64, mingw32
 ui       RStudio
 language (EN)
 collate  English_Australia.utf8
 ctype    English_Australia.utf8
 tz       Australia/Sydney
 date     2023-11-28
 rstudio  2023.09.1+494 Desert Sunflower (desktop)
 pandoc   2.9.2.1 @ C:\\Users\\87054612\\AppData\\Local\\Pandoc\\pandoc.exe

─ Packages ────────────────────────────────────────────────────────────────────────────────────────────────────────────────
 package     * version  date (UTC) lib source
 cachem        1.0.6    2021-08-19 [1] CRAN (R 4.2.0)
 callr         3.7.3    2022-11-02 [1] CRAN (R 4.2.2)
 cli           3.6.0    2023-01-09 [1] CRAN (R 4.2.2)
 crayon        1.5.2    2022-09-29 [1] CRAN (R 4.2.2)
 devtools      2.4.5    2022-10-11 [1] CRAN (R 4.2.2)
 digest        0.6.31   2022-12-11 [1] CRAN (R 4.2.2)
 ellipsis      0.3.2    2021-04-29 [1] CRAN (R 4.2.0)
 fastmap       1.1.0    2021-01-25 [1] CRAN (R 4.2.0)
 fs            1.6.1    2023-02-06 [1] CRAN (R 4.2.3)
 glue          1.6.2    2022-02-24 [1] CRAN (R 4.2.0)
 htmltools     0.5.4    2022-12-07 [1] CRAN (R 4.2.2)
 htmlwidgets   1.6.1    2023-01-07 [1] CRAN (R 4.2.2)
 httpuv        1.6.8    2023-01-12 [1] CRAN (R 4.2.2)
 later         1.3.0    2021-08-18 [1] CRAN (R 4.2.0)
 lifecycle     1.0.3    2022-10-07 [1] CRAN (R 4.2.2)
 magrittr      2.0.3    2022-03-30 [1] CRAN (R 4.2.0)
 MASS          7.3-58.1 2022-08-03 [2] CRAN (R 4.2.2)
 memoise       2.0.1    2021-11-26 [1] CRAN (R 4.2.0)
 mime          0.12     2021-09-28 [1] CRAN (R 4.2.0)
 miniUI        0.1.1.1  2018-05-18 [1] CRAN (R 4.2.2)
 pkgbuild      1.4.0    2022-11-27 [1] CRAN (R 4.2.2)
 pkgload       1.3.2    2022-11-16 [1] CRAN (R 4.2.2)
 prettyunits   1.1.1    2020-01-24 [1] CRAN (R 4.2.0)
 processx      3.8.0    2022-10-26 [1] CRAN (R 4.2.2)
 profvis       0.3.7    2020-11-02 [1] CRAN (R 4.2.1)
 promises      1.2.0.1  2021-02-11 [1] CRAN (R 4.2.0)
 ps            1.7.2    2022-10-26 [1] CRAN (R 4.2.2)
 purrr         1.0.1    2023-01-10 [1] CRAN (R 4.2.2)
 R6            2.5.1    2021-08-19 [1] CRAN (R 4.2.0)
 Rcpp          1.0.10   2023-01-22 [1] CRAN (R 4.2.2)
 remotes       2.4.2    2021-11-30 [1] CRAN (R 4.2.0)
 rlang         1.1.0    2023-03-14 [1] CRAN (R 4.2.3)
 rstudioapi    0.14     2022-08-22 [1] CRAN (R 4.2.2)
 sessioninfo   1.2.2    2021-12-06 [1] CRAN (R 4.2.0)
 shiny         1.7.4    2022-12-15 [1] CRAN (R 4.2.2)
 signal        0.7-7    2021-05-25 [1] CRAN (R 4.2.0)
 stringi       1.7.12   2023-01-11 [1] CRAN (R 4.2.2)
 stringr       1.5.0    2022-12-02 [1] CRAN (R 4.2.2)
 urlchecker    1.0.1    2021-11-30 [1] CRAN (R 4.2.2)
 usethis       2.1.6    2022-05-25 [1] CRAN (R 4.2.2)
 vctrs         0.5.2    2023-01-23 [1] CRAN (R 4.2.2)
 xtable        1.8-4    2019-04-21 [1] CRAN (R 4.2.2)

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Version

Install

install.packages('trajr')

Monthly Downloads

339

Version

1.5.1

License

MIT + file LICENSE

Issues

Pull Requests

Stars

Forks

Maintainer

Last Published

November 29th, 2023

Functions in trajr (1.5.1)

TrajDirectionAutocorrelations

Direction autocorrelation
TrajEmax

Trajectory straightness index, E-max
TrajDuration

Trajectory duration
TrajGetNCoords

Trajectory number of coordinates
TrajDistance

Trajectory distance
TrajFromCoords

Create a Trajectory Object
TrajMerge

Combine multiple trajectories into a single whole trajectory
TrajGenerate

Generate a random trajectory
TrajFromTrjPoints

Create a trajectory from a subset of another
TrajDirectionalChange

Directional change (DC)
TrajGetTimeUnits

Trajectory temporal units
TrajExpectedSquareDisplacement

Trajectory expected square displacement
TrajRediscretize

Resample a trajectory to a constant step length
TrajSmoothSG

Smooth a trajectory using a Savitzky-Golay filter
Traj3DLength

3D trajectory length
TrajRotate

Rotate a trajectory
TrajGetFPS

Trajectory frames-per-second
TrajSpeedIntervals

Calculate speed time intervals
TrajMeanVectorOfTurningAngles

Mean vector of turning angles
TrajSplit

Split a trajectory into multiple sections
TrajSplitAtFirstCrossing

Split a trajectory into two parts, separated at the first boundary crossing
TrajScale

Scale a trajectory
points.Trajectory

Add Trajectory points to a plot
TrajMeanVelocity

Trajectory mean velocity
Traj3DDistance

3D Trajectory distance
TrajDAMinMax

First direction autocorrelation minimum/maximum
TrajAngles

Turning angles of a Trajectory
TrajGetUnits

Trajectory spatial units
TrajStepLengths

Trajectory step lengths
trajr-package

trajr: Animal Trajectory Analysis
TrajConvertTime

Converts a delimited time string to a numeric value
TrajResampleTime

Resample a trajectory to a constant time interval.
TrajInPolygon

Test whether each of the points in a trajectory lie inside a polygon
TrajReverse

Reverse a trajectory
TrajTranslate

Translate a trajectory
plot.TrajSpeedIntervals

Plot method for trajectory speed intervals
TrajVelocity

Velocity of a trajectory
TrajDerivatives

Calculates trajectory speed and change of speed
TrajStraightness

Straightness of a Trajectory
TrajLength

Trajectory length
TrajLogSequence

Logarithmically spaced sequence
TrajFractalDimension

Fractal dimension of a trajectory
TrajsStatsReplaceNAs

Replace NAs in a data frame
plot.Trajectory

Plot method for trajectories
TrajFractalDimensionValues

Fractal dimension calculation
TrajSinuosity

Sinuosity of a trajectory
TrajsStepLengths

Step lengths of multiple trajectories
lines.Trajectory

Add Trajectory lines to a plot
TrajSinuosity2

Sinuosity of a trajectory
plot.TrajDirectionAutocorrelations

Plot method for direction autocorrelation
TrajsBuild

Construct multiple trajectories
TrajsMergeStats

Merge trajectory characteristics
Traj3DSmoothSG

Smooth a 3D trajectory using a Savitzky-Golay filter
Traj3DFromCoords

Create a 3D Trajectory Object
Traj3DRediscretize

Resample a 3D trajectory to a constant step length
Traj3DResampleTime

Resample a 3D trajectory to a constant time interval
ElapsedTimeProgressBarFn

A general purpose progress bar that reports elapsed time rather than number of items
Traj3DStraightness

Straightness of a 3D Trajectory
Traj3DStepLengths

3D trajectory step lengths
TrajAcceleration

Approximates the acceleration of a trajectory