maximize-window-vertically in emacs

maximize-window.el

(defun maximize-window-in-direction (&optional horizontally)
  "Maximize window.
Default vertically, unless HORIZONTALLY is non-nil."
  (interactive)
  (unless (seq-every-p
	   (apply-partially #'window-at-side-p nil)
	   (if horizontally '(left right) '(top bottom)))
    (let* ((buf (window-buffer))
	   (top-size (window-size (frame-root-window) (not horizontally)))
	   (size (min (/ top-size 2) (window-size nil (not horizontally))))
	   (dir (if horizontally
		    (if (window-at-side-p nil 'top) 'above 'below)
		  (if (window-at-side-p nil 'right) 'right 'left))))
      (delete-window)
      (set-window-buffer
       (select-window (split-window (frame-root-window) (- size) dir))
       buf))))

(bind-key "C-x 7" (lambda () (interactive (maximize-window-in-direction 'horizontal))))
(bind-key "C-x 9" #'maximize-window-in-direction)