gyoto-bin software package provides General relativistic ray-tracing command-line interface, 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 gyoto-bin
gyoto-bin is installed in your system.
Make ensure the gyoto-bin package were installed using the commands given below,
$ sudo dpkg-query -l | grep gyoto-bin *
You will get with gyoto-bin package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Science |
| Package | gyoto-bin |
| Version | 1.1.1-2 |
| Description | General relativistic ray-tracing command-line interface |
| Sub Section | Science |