Convert a collapsed distribution into a expanded, raster equivalent

This function converts a collapsed distribution in which the first (and possibly only) dimension represents all the locations in the model into an expanded, raster state in which the first two dimensions represent the locations of the cell in physical space (row, col) and are thus suitable for plotting or conversion into spatial objects.

Usage

expand_distr(distr, bf)

Arguments

distr

Either a vector representing a single distribution with one value per location in the model or a matrix in which each column is such a vector. Higher dimensions are allowed (but unlikely); in all cases the first dimension is for locations in the model.

bf

A BirdFlow model

Value

An expanded version of distr with one additional dimension, in which the first two dimensions are rows and columns in space (a raster) and replace the first dimension in the input.

Details

In its collapsed form a single distribution is stored as a vector. Each value can be interpreted as the relative abundance or probability of finding a bird at the corresponding location. A special case is when the vector has mostly 0's and a single 1 in which case it represents a single position of a bird or group of birds, a very concentrated distribution.

Additional dimensions can represent multiple timesteps and/or multiple individual birds, model runs etc.

The location information in the collapsed distribution is not easily accessible as position in the vector is ordered based on row-major ordered unmasked cells in the extent, and R uses column-major order.

As of May 2023 this is now an internal function replaced by rasterize_distr(format = "numeric").