ngspice software package provides Spice circuit simulator, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install ngspice
ngspice is installed in your system.
Make ensure the ngspice package were installed using the commands given below,
$ sudo dpkg-query -l | grep ngspice *
You will get with ngspice package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | Electronics |
| Package | ngspice |
| Version | 24-1.1ubuntu2 |
| Description | Spice circuit simulator |
| Sub Section | Electronics |