# EquationExplorer

## Frequently Asked Questions

### What can I graph with it?

*EquationExplorer* can graph most algebraic equations, both implicit and explicit.

Here are a few interesting implicit equations to get you started:

- Circle
- Ellipse
- Superellipse
- Cardioid
- Limacon
- Elliptic Curve
- Mordell Curve
- Heart Curve
- Quadrifolium
- Knot Curve

It also supports non-implicit functions, such as:

### What special functions can be used in equations?

- sin — Sine (radians)
- cos — Cosine (radians)
- tan — Tangent (radians)
- atan — Inverse Tangent (result in radians)
- acos — Inverse Cosine (result in radians)
- asin — Inverse Sine (result in radians)
- round — Round to nearest integer
- sqrt — Square Root
- abs — Absolute Value
- ln — Natural Logarithm

### How can I save a graph as an image?

Right click on the graph and choose "Save Image As..." (In Firefox). Other browsers may have similar options.

### What happens when I use the variable `m` in an equation?

Buttons will appear below the input to allow you to adjust the value of `m`. That value will be substituted back into the equation at each use of the variable. This allows you to easily experiment on how a change to a constant will affect the graph.

Many of the example equations listed above use this feature.

### Which browsers are supported?

This application performs the best in the following browsers:

- Firefox 3.5+
- Google Chrome
- Safari 4+

These browsers also work, though it may be slow or lack certain features:

- Firefox 3.0+
- Opera

### Why isn't Microsoft Internet Explorer supported?

Internet Explorer does not support the <canvas> element this application uses for its graphing. Additionally, the Javascript engine in IE is much too slow to handle real-time rendering.

Try another browser and you'll have a better experience on this and other sites.

### How does it work?

You can read about the inner workings of EquationExplorer on my blog post.

### Can I re-use the parser or graphing engine elsewhere?

The source is released under the GPL and can be found on github. Relevant files are:

- tdop_math.js - the parser
- tokens.js - the TDOP tokenizer
- graph.js - the graphing engine
- ui.js - the user interface

You can experiment with the parser at its test page

### Have another question?

Post on the Feedback page