Using Move package and having trouble with ext argument.

General
2

Without a reprex (see the FAQ), this is difficult to debug. So, we'll just look at the function signature.

## S4 method for signature 'dBGBvariance,RasterLayer,numeric'
dynBGB(move, raster, locErr, timeStep, ...)
## S4 method for signature '.MoveTrackSingle,RasterLayer,numeric'
dynBGB(move, raster, locErr, margin, windowSize, ...)
## S4 method for signature '.MoveTrackSingle,numeric,ANY'
dynBGB(move, raster, locErr, ext, ...)
## S4 method for signature '.MoveTrackSingle,missing,ANY'
dynBGB(move, raster, locErr, dimSize, ext, ...)

To begin \dots is not implmented, so we can set that aside.

The move parameter first, then. It must be a move or dBGBvariance object and

move_obj is given as its argument. Confirm that is conforms to the requirement that it be

a move or dBGBvariance object. This object must be in a projection different to longitude/latitude (one suitable for euclidean geometry), use spTransform to transform your coordinates.

by using

check(move_obj)

The second argument raster is missing. If used it must be

a RasterLayer object or a numeric value. If a RasterLayer is provided the dynBGB starts to calculate the UD based on that raster. If a numeric value is provided it is interpreted as the resolution of the square raster cells (in map units); the according raster will be calculated internally.

but if omitted dimSize must be provided

numeric. dimSize is only used if raster is not set. dimSize is interpreted as the number of cells along the largest dimension of the track. The according raster will be calculated internally.

The third argument locErr is also missing. It must be

a single numeric value or vector of the length of coordinates that describes the error of the location (sender/receiver) system in map units. Or a character string with the name of the column containing the location error can be provided.

timestep is optional, and if is not provided, it has a default value there is a default

it correspond[s] to the size of the timer intervals taken for every integration step (in minutes). If left NULL 20.1 steps are taken in the shortest time interval.

margin is needed if move_obj is a raster layer

The margin used for the behavioral change point analysis. This number has to be odd.

windowSize is also used for a raster layer

The size of the moving window along the track. Larger windows provide more stable/accurate estimates of the brownian motion variance but are less well able to capture more frequent changes in behavior. This number has to be odd.

window is not one of the permitted arguments

ext is required when the move argument is numeric rather than a raster or in conjunction with the dimSize argument and it must

Describes the amount of extension of the bounding box around the animal track. It can be numeric (same extension into all four directions), vector of two (first x, then y directional extension) or vector of four (xmin, xmax, ymin, ymax extension). Only considered in combination with a numeric raster argument or the dimSize argument.

dimSize is used when the move argument is not a raster. It is

numeric. dimSize is only used if raster is not set. dimSize is interpreted as the number of cells along the largest dimension of the track. The according raster will be calculated internally.

So, there's some care here that needs be taken with using dynBGB(). Argument choice depends on whether a raster-like object is being used and that dictates the combination of required and optional arguments that are available and the user must consider whether the optional arguments can be derived from objects provided to the function.