altree-examples software package provides example files for ALTree, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install altree-examples
altree-examples is installed in your system.
Make ensure the altree-examples package were installed using the commands given below,
$ sudo dpkg-query -l | grep altree-examples *
You will get with altree-examples package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Science |
| Package | altree-examples |
| Version | 1.3.1-4 |
| Description | example files for ALTree |
| Sub Section | Science |