Showing line numbers in IPython/Jupyter Notebooks

Question

Error reports from most language kernels running in IPython/Jupyter Notebooks indicate the line on which the error occurred; but (at least by default) no line numbers are in

Answer 1

On IPython 2.2.0, just typing l (lowercase L) on command mode (activated by typing Esc) works. See [Help] - [Keyboard Shortcuts] for other shortcuts.

Also, you can set default behavior to display line numbers by editing custom.js.