Trevor Pythagoras

Whilst you should always try to sketch any graphs you need to sketch yourself, since this is the only way you’ll get to understand why graphs look the way they do, it is often useful to use a computer program to check against. Here are two online graph sketching applets that you can use for free. They give good results (especially for programs you can run in a browser without paying for) and can be useful for checking the graphs you have sketched. Note that these programs both require your computer has java installed to run (you probably do and they contain instructions on where to get the required version from if you don’t).

Please note: I am not responsible for the content of external websites and cannot guarantee that these features will be working, available or accurate.

Shodor Graph Sketcherr

This enables you to plot most functions in Cartesian form. It requires you to enter the graph as a function of x and then clicking “graph” will plot it for you. Using the tools in the top right hand corner you can zoom in/out and more around the graph, you can also adjust the axis.

A screen shot of the graph y=x^2 using the Shodor Graph Sketcher

Polar Co-ordinates Graph Sketcher

This applet will allow you to sketch graphs using polar co-ordinates. You can enter a range and your graph as a function of t (the angle). It also allows you to zoom in and out of the graph and includes a list of the functions it supports and how to enter them.

Screenshot of the graph r=sin(t) as drawn by the polar co-ordinates graph sketcher