I am plotting some model outputs in QGIS and let's say I have got a given number of polygons and for each one a value which can be negative OR positive.
I need to assign to each polygon's value a colour and it needs to change between positive and negative, e.g. red for negative and green for positive.
I think that the
Graduated option is the one that best suits my needs but I don't know how?
Also if this can be done, how can I apply it automatically to other layers? I have quite a few maps to do, and to do it manually would take a long time.
The idea is something like this but with polygons: