gnuplot5-qt software package provides transitional package, you can install in your Ubuntu 17.04 (Zesty Zapus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install gnuplot5-qt
gnuplot5-qt is installed in your system.
Make ensure the gnuplot5-qt package were installed using the commands given below,
$ sudo dpkg-query -l | grep gnuplot5-qt *
You will get with gnuplot5-qt package name, version, architecture and description in a table
| Distro | Ubuntu 17 04 zesty zapus |
| Section | Old Libraries |
| Package | gnuplot5-qt |
| Version | 5.0.5+dfsg1-4ubuntu1 |
| Description | transitional package |
| Sub Section | oldlibs |