where do I find the definition of class objects in spatstat

I would 开发者_开发技巧like to know what kind of information does an object of class Spatialpolygons has versus an object of class Polygons.

If you open help pages for Polygon or SpatialPolygons (doesn't really matter, it will lead you to the same page), you can click on SpatialPolygons-class and Polygons-class links. There, you can see which slots each class contains.

Polygon-class as an example:

Slots

ringDir:
    Object of class "integer"; the ring direction of the ring (polygon) coordinates, holes are expected to be anti-clockwise 
labpt:
    Object of class "numeric"; an x, y coordinate pair forming the label point of the polygon 
area:
    Object of class "numeric"; the area of the polygon 
hole:
    Object of class "logical"; does the polygon seem to be a hole 
coords:
    Object of class "matrix"; coordinates of the polygon; first point should equal the last point