How to recover a notebook emptied after kernel crash?

Question

While working in an ipython notebook, eventually I had to Ctrl+C as the kernel seemed to be halted.

The console gave me a message like:

[NotebookApp] Kernel  shutdown: 5faa86bf-........f6 
[NotebookApp] Kernel  shutdown: 71........22 
[NotebookApp] ....

(I had three notebooks running)

But something went wrong and my notebook file.ipynb is empty (actually only the one I was actively using).

Is there a way to recover that file before it was deleted? Some place where automatically-saved o manually-saved versions are stored?

(Running python 2.7 (Anaconda) in Windows 7)

Answer 1

You can check in .ipynb_checkpoints/ in the folder where your notebook was for recent enough version of IPython.

Answer 2

If none of the above helped, I found a workaround to recover most of the changes I did since the last checkout - by simply calling this command in your notebook:

%history -g

If you want your IPython history in a plain-text file, you can export it yourself.

You can also do it for a specific filename:

%history -g -f filename 

What does -g do? – Without -g it exports the history for the current session. With -g it exports history for all sessions.