How to split the display vertically when 2 horizontal windows exist

Question

Could anyone please give me a hand to split the display vertically to create a third window that spans across the entire frame when there are two pre-existing windows side by side?

I often have an open window, then I do an org-capture to create a todo, but then I'm not sure about the date, so I open the calendar which gets scrunched underneath Window # 1 -- I'd like the calendar to span the length of the frame.

Example:

Window # 1    |     org-capture window

Then, split screen vertically:

Window # 1    |     org-capture window
______________________________
           calendar

Answer 1

Upon examining calendar.el, I saw that much work had been done by the developer(s) to select the window location / size. Rather than using defalias and modifying the functions in calendar.el and/or org-capture.el, the following is a simple method to display the calendar across the entire bottom of the frame when using org-capture.

EDIT:  Replaced (windmove-left) and (windmove-right) with (other-window 1), which is needed when using the lawlist-org-capture function on smaller resolution screens. org-capture splits the screen vertically instead of horizontally when the user has a lower resolution display, and visa-versa on a higher resolution display. (other-window 1) works for both situations.

(defun lawlist-org-capture ()
  (interactive)
  (org-capture)
  (setq lawlist-org-restore-a (buffer-name))
  (other-window 1)
  (setq lawlist-org-restore-b (buffer-name))
  (delete-other-windows)
  (calendar)
  (windmove-up)
  (split-window-horizontally)
  (switch-to-buffer lawlist-org-restore-b)
  (other-window 1)
  (switch-to-buffer lawlist-org-restore-a) )