I am trying to do make a graph which shows frequency of geographical locations in the UK being used in an academic paper. I have made a column of frequencies and a column of corresponding postal codes and have highlighted these to try to make a map graph.
However, the graph that comes up is of the UK but is all grey, the other axis comes up as frequency with different colour gradients to show different frequencies that I have inputted but the colour is not showing up on the all grey map of the UK. Does anyone know why it is doing this?
Thank you so much to anyone in advance who might know how to help!