I'm plotting a figure with Y axis (Amount of products) vs. X axis (time as
seconds). At the same figure, i'd like to add a second X axis, which shows
the time as hours. This axis can be on the top of the figure, or below the
exising X axis. Anyone has the idea how to add this axis? I researched the
help center, it seems we can only add a second Y axis, is this true?