[Answer]-MATLAB to web app

A cheap and somewhat easy way (with limited functionality) would be:

Install MATLAB on your server, or use the MATLAB Compiler to create a stand alone executable (not sure if that comes with your version of MATLAB or not). If you don’t have the compiler and can’t install MATLAB on your server, you could always go to a freelancing site such as elance.com, and pay someone $20 to compile your code for you into a windows exe file.

Either way, the end goal is to make your MATLAB function callable from the command line (the server will be doing the calling) You could make your input arguments into the slider value, and the .mat files you want to open, and the compiled version of MATLAB will know how to handle this. Once you do that, have the code create a plot and save an image of it. (using getframe or other figure export tools, check out FEX). Have your server output this image to the client.

Tah-dah, you have a crappy low cost work around!

I hope this helps , if not, I apologize!

You could always just host the MATLAB code and sample .mat on a website for people to download and play with on their own machines if they have a MATLAB license. If you are looking at having some sort of embedded app on your website you are going to need to rewrite your code in another language. The project sounds doable in python using the packages you mentioned however hosting it online will not be as simple as running a program from your command line. Django would help you build a website but I do not think that it will allow you to just run a python script in the browser.