I would like to adjust the colorbar below to show -X on the left and a zero below the center.
I managed to get the X by using:
fig.colorbar(... frame=["y+lX"] ...)
How can I annotate
-X at the other end of the colorbar and a 0 in the center?
My other idea was to use the -L option GMT has to customise the labels by adding a semi-colon and the label name at the end of a line in the CPT file (as shown here). However, it looks like the -L option is not yet implemented in pygmt…?
Any help is much appreciated!