Matlab's graphical data tip precision

The graphical data tip in Matlab allows you to visualize the values of a point in a plot.
It comes with a certain decimal precision level already set as default (4 decimal digits).
You can change the default number of decimal digits.
See at the following Webpage,

http://www.cs.washington.edu/homes/dhalperi/useful.html

(thanks to Daniel Halperin for the suggestion).

2017 update

The previous instructions are valid for Matlab R2014a and older versions.
For Matlab R2014b and newer version, follow the suggestions from the following threads:

https://stackoverflow.com/questions/25477401/matlab-permanently-set-text-update-function-for-data-cursor-in-figures/39330765#39330765

Thanks to Michael Hirsch for pointing this out.