Modelling and Simulation Laboratory

Clicking on the links below will bring up a new window with an equation solving tool in it. You can then type your equations, in a variety of formats, into boxes, and click on the solve button. Most have built in examples for you to try.

Note that:

To use these you must have JavaScript enabled on your browser. This may produce security warnings. For those that draw graphs you should also have Java.
Saving the web page will not save the answers which appear in the boxes. However you can use the usual select, copy and paste mechanisms to copy information into another application such as Notepad or Excel.
Tools are provided for educational purposes only. If you wish to use them to solve real problems you are responsible for validating the results. The authors specifically disclaim all responsibility for any use made of this free software.

Nonlinear Algebraic equations

The following are somewhat more complicated to use and are not recommended for the inexperienced.

Alternative ordered equation solver
A very flexible solver but requires equations to be written in JavaScript notation.
Multivariable a.e. solver using quasi-Newton method
Solves iteratively for all unknowns simultaneously. It requires an initial estimate for each unknown and can be sensitive to this choice.

A range of linear equation solvers.

ODEs and DAEs

Optimisation and data fitting

Background to Modelling

JavaScript Programming

Even if you have never written programs before, you might like to try learning JavaScript, the language in which all of the above tools have been written. You can write the programs on your own computer, and run them in any web browser.

Here is an introductory mini-course in JavaScript programming.

If you have some prior knowledge of a programming language you can look at my JavaScript conversion course. This is mainly intended for Fortran programmers but if you know Basic or (especially) C you should also be able to follow it.