Free math graphing software
By Murray Bourne, 05 Oct 2010
I received a delightful mail from Morgan, a 95-year old reader. He said:
I'm interested in a 3D Contour Grapher. For personal use. I am 95.
I'm impressed with the number of retirees who maintain an interest in mathematics. The learners are the ones who will stay young.
Here are two recommendations, Morgan. The first is the easiest to use and most appropriate for you.
Winplot by Richard Parris (deceased) of Philips Exeter Academy has been around for many years.
The good: Winplot can plot a large range of function types, including explicit and implicit functions, vector fields, parametric equations and 3-D plots, as well as contour plots as you can see below. It comes in many language versions.
The bad: Windows only (no Mac or Linux versions).
2. Graphics Layout Engine
Graphics Layout Engine is an open source offering, but not for the faint-hearted.
The good: It produces nice clean graphs and can handle a wide range of function types, including vector fields, split functions and statistics. It can also do 3-D plots, fractals and electronic circuit diagrams. GLE can output to PDF, EPS, PS, SVG (scalable vector graphics), PNG and JPEG (for the Web).
The bad: It is a scripted language. That is, you need to write your script in a text editor to get your graphs - there is no simple graphical user interface. You may also need to download other required software (like Ghostscipt, which is an interpreter for PostScript and PDF).
I wrote an earlier article Graphs using free math software which you may find interesting.
Also, GeoGebra remains a favorite. I wrote an introductory review here: GeoGebra math software - a review, which contains relevant links.
GeoGebra doesn't do contour plots (as far as I can work out), but it is a great piece of free graphing software.
So Morgan, I hope you find all that useful.
See the 12 Comments below.