plot_walk: Plots walk paths using ggplot.
In mbedward/walkies: Random walks

Plots one or more walk.data object paths (generated by make_walk).

1 2	plot_walk(w, colour = c("none", "direct", "path"), legend = FALSE, by.id = FALSE, nrow = NULL, ncol = NULL)

`w`	Either a single `walk.data` object, or a list of such objects.
`colour`	The variable to use for colouring within each walk path: `'direct'` for direct distance to start point; `'path'` for distance along path; `'none'` for no colouring
`legend`	If `TRUE`, a legend is added to the plot when path colouring is used. Ignored if `colour` is `'none'`.
`by.id`	If `TRUE`, plots are facetted by the `walk.data$id` field. If `FALSE` (default), a single plot is produced.
`nrow`	If `by.id` is `TRUE`, this argument can be used to set the number of rows of facetted plots.
`ncol`	If `by.id` is `TRUE`, this argument can be used to set the number of columns of facetted plots. See `link{ggplot2::facet_wrap}`.