If you dont have Mathematica on your computer, you can still use it to run Mathemtica on a Raspberry Pi.
The trick is to use VNC, and works from any computer with a terminal and a VNC viewer. I am only familiar with Macs and iPads, which have them. Ideas are taken from
You need to know the IP address of your Pi. I found mine with Preferences/WiFi Configuration. My Pi has IP 192.168.0.41 .
I just set up a new Raspberry Pi 2. All of the following can be done from your computer.
From a terminal on your computer, log into your Pi with
ssh pi:192.168.0.41 (use your IP, of course)
with password raspberry.
If you havent done it, upgrade the Wolfram engine with
sudo apt-get update && sudo apt-get install wolfram-engine
Install tightvncserver with
sudo apt-get install tightvncserver
A password has to be chosen. Not knowing anything, I chose raspberry. Start tightvncserver with
Install the free VNC Viewer (or other VNC viewer) on your computer. Start it and connnect to the VNC server (use your IP)
giving the VNC password. The Desktop of your Pi magically opens up on your computer. You can now run Mathematica (or any other Pi program). You no longer need a monitor for your Pi. The steps are log into the Pi, start tightvncserver, then connect with VNC Viewer.
(A link on the above link explains how to eliminate the first step and auto-start tightvncserver when the Pi is booted.)