Why are there gaps on the heat map that cannot be deleted

Dear friends:
I am using ggplot2 to draw a heat map, but when the time variable is used as the horizontal axis, there is always a white gap as shown in the figure below. I have tried various methods but cannot delete it.
I earnestly request your guidance, thank you.

plotda <- xd[dtime<=as.Date('1962-3-1'),]
  facet_grid(group~. )+

I'd try changing panel spacing to zero by adding

+ theme(panel.spacing = unit(0,"cm"))

Thank you very much for your answer, but multiple vertical gaps still exist.

for further assitance please provide a reprex

This topic was automatically closed 42 days after the last reply. New replies are no longer allowed.

If you have a query related to it or one of the replies, start a new topic and refer back with a link.