Re: [GRASS-stats] Why does rgrass7::writeVECT() silently add a cat column if it doesn't exist?

Hi Vero, as I understand it, vector files in GRASS need a key column if they have an attribute table. But I don't see that this has to be a column named 'cat'. However, GRASS is quite inconsistent here. Some functions ensure the existence of a 'cat' column, such as v.db.dropcolumn (just gives

Re: [GRASS-stats] Why does rgrass7::writeVECT() silently add a cat column if it doesn't exist?

Hello Tobias, The cat colum is the ID that GRASS uses for vectors, hence this is expected and right. The same happens if you import a gpgk or shape or any other vector file into GRASS. See https://grass.osgeo.org/grass78/manuals/vectorintro.html for further info HTH, Vero El mié, 20 oct 2021

[GRASS-stats] Why does rgrass7::writeVECT() silently add a cat column if it doesn't exist?

Dear list, when I use in R the writeVECT() command the resulting map in GRASS got the 'cat' column silently added to its attribute table if it didn't exist. The vector object in question was previously imported to R via readVECT() and had a different column defined as key column. Is this