moving from sp maptools to sf

R. Bivand send a message in september 2021 annoucing the end of maptools, rgeos etc in and 2023. sp will works but it is probable that sf will replace sp in the future. Here we highlight the main changes in ade packages that we must consider in the future to manage spatial data.

We will need to develop new branches in ade4, adegraphics and adespatial to develop these changes.

In the past, ade4 implemented area and neig classes. Now they can also use sp classes for spatial data and nb / listw (from spdep) for spatial neighbouring and weighting matrices

In the future, we should:

• remove neig and area objects in ade4 data sets
• remove associated arguments neig and area from ade4 graphical functions (check also for argument contour)
• replace Spatial* objects by sf objects in data sets
• reimplement adegraphics functions to deal with sf objects instead of sp

see the discussion at https://github.com/friendly/Guerry/issues/1#issuecomment-918208935 for more details

Bellow is the list of ade4 data containing sp objects : atlas, avijons, buech, butterfly, capitales, elec88, ggtortoises, irishdata, julliot, jv73, kcponds, mafragh, t3012, vegtf