During the course of the last two lessons you have read a number of files into Emacs. Now is a good time for a brief digressions to explain a few more aspects of Emacs.
Pull down the Buffers menu of Emacs. You will see a list of the files that are currently contained in an Emacs buffer. ``Buffer'' is the Emacs term for a file that is displayed for editing. Notice that the names of all of the files that you have read into Emacs today are displayed. By selecting one of those files, you can resume editing it.
You can split an Emacs window into two pieces so that you can view more than one buffer at a time. You have already seen this happen when you compile a file---Emacs splits the window so that the compiler messages can appear in a separate buffer. The command to split a window is Ctrl-x 2, and the command to unsplit a window is Ctrl-x 0.
Emacs will also let you do something better than splitting a window---it will let you open up a new window. To open a new window, select the New Frame option from the File menu.
To get rid of a window, select the Delete Frame option from the File menu.
Now try this. Use the window opening commands that you have just learned to open an extra window. Notice that the new window has its own menu bar. Arrange for the original window to display ``examples/average1.f'' (you may have to use the buffer changing commands if something different is currently displayed) and for the new window to display ``examples/average2.f''. If you like, resize the windows so that they fit nicely on the screen.
Hamlet Project