Ubuntu – jupyter notebook does not start off on Ubuntu 16.04

I have recently upgraded to Ubuntu 16.04 and installed jupyter notebook following either of the standard procedures indicated here. The installation procedure runs smoothly and completes without exceptions (both with pipand anaconda). At the moment of running the notebook I get, though

$ jupyter notebook
-sh: jupyter: command not found

and similarly

$ which jupyter

does not give back any output, as if it were nowhere to be found. However, manually looking into all the possible locations I have found that into ~/.local/lib the notebook does start off correctly with

$ ~/.local/lib jupyter notebook

and it is the only way I can operate it.

• How can I change the path where jupyter is installed, in order to launch it normally without having to search into the hidden folders?

• I have tried to un-install it in order to install it again with $sudo apt-get remove --purge but since the path is hidden it does not recognize the application as already installed, hence the un-installation does not proceed.

If it can be useful, I have upgraded the Ubuntu version following a new installation from scratch, therefore I doubt conflict with existing versions and previous paths may be the cause.