gsmc software package provides Smith Chart calculator for impedance matching, 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 gsmc
gsmc is installed in your system.
Make ensure the gsmc package were installed using the commands given below,
$ sudo dpkg-query -l | grep gsmc *
You will get with gsmc package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Ham Radio |
| Package | gsmc |
| Version | 1.2.1-1 |
| Description | Smith Chart calculator for impedance matching |
| Sub Section | hamradio |