dimension: optional: numbers or names of dimension(s) to get per-dimension type
Returns
if dimension is not specified, return the spatial raster type: one of NA (if the object does not have raster dimensions), "curvilinear", "rectilinear", "affine", or "regular". In case dimension(s) are specified, return one of "regular", "rectilinear"
(irregular but numeric), or "discrete" (anything else).
Details
categories "curvilinear" and "affine" only refer to the relationship between a pair of spatial (raster) dimensions.