# Changes to the `trajr`

package

## trajr 1.4.0

- Allow the creation of trajectories with 0 points in
`TrajFromCoords`

.
- Fixed bug in TrajSpeedIntervals: no intervals were being returned if
the entire trajectory qualified as an interval.
- Fix bug in plot.TrajSpeedIntervals: time (x-axis) didn’t handle
trajectories with a non-zero starting time.
- Added functions to assist in simulating trajectories that are
bounded or vary spatially in some way. The new functions are
`TrajInPolygon`

, `TrajSplit`

,
`TrajMerge`

and `TrajSplitAtFirstCrossing`

.
- Added functions to calculate velocity and acceleration:
`TrajVelocity`

and `TrajAcceleration`

. The
documentation for `TrajDerivatives`

has been updated to state
that the `acceleration`

returned is not really acceleration,
rather it is change in speed over time.
- Added argument
`diff`

to `TrajSpeedIntervals`

to control how speed is calculated. Default is “backward” so the
function is backwards-compatible, although “central” is usually a better
choice.

## trajr 1.3.0

- Detect and report some invalid parameter values.
- Altered handling of parameter
`readcsvFn`

to
`TrajsBuild`

to make it possible to use
`readr::read_csv`

without a wrapper function.
- Added function
`TrajResampleTime`

to resample a
trajectory to fixed step times.
- Added parameters
`start.pt.pch`

and
`start.pt.col`

to plotting functions.
- Added parameter
`dt`

to `TrajTranslate`

- Fix vertical extents of rectangles in
`plot.TrajSpeedIntervals`

to handle non-default ylim
values.
- Added optional progressbar to
`TrajsMergeStats`

.
- TrajsMergeStats now passes the arguments
`stringsAsFactors = FALSE`

to rbind. This prevents incorrect
behaviour and the warning “invalid factor level, NA generated” if one or
more of your statistics are characters.
- Enhanced
`TrajRotate`

to allow absolute rotation and
arbitrary origin of rotation.

## trajr 1.2.0

- Added start.pt.cex parameter to function
`lines.Trajectory`

.
- Added function
`TrajConvertTime`

.

## trajr 1.1.0

- Added correct citation.
- Fixed:
`plot.TrajSpeedIntervals`

was not passing
additional arguments (`...`

) to `plot`

.
- Added: functions
`TrajDuration`

,
`TrajMeanVelocity`

, `TrajTranslate`

.
- Added
`translateToOrigin`

parameter to function
`TrajsBuild`

.