Thread: 3D graphing software (free? linux-compatible?)

Hello everyone, I'm a high school student and I'm looking for some software which will allow me to graph lines and surfaces in 3D, and which will also perform some calculations such as finding intersections of lines and/or surfaces. I have been working on a research project which involved graphing lines and finding their intersections: initially i used a program called GeoGebra, which is very simple but works well. However, extending the investigation I would like to find intersections of plains (for a large range of functions; by hand just won't cut it). I'd prefer the software to be free (even better is it's open source) and also preferably linux compatible. However, just general information on good programs out there would be helpful.
I tried gnuplot, but looking through the documentation I can't find any mention of calculating intersections, and I suspect it is not possible. Is this right?

Thanks in advance.

Dan

Update: Any comments on Freemat or Sage (which I have only just found and downloaded)?

Originally Posted by danielstrong52

Hello everyone, I'm a high school student and I'm looking for some software which will allow me to graph lines and surfaces in 3D, and which will also perform some calculations such as finding intersections of lines and/or surfaces. I have been working on a research project which involved graphing lines and finding their intersections: initially i used a program called GeoGebra, which is very simple but works well. However, extending the investigation I would like to find intersections of plains (for a large range of functions; by hand just won't cut it). I'd prefer the software to be free (even better is it's open source) and also preferably linux compatible. However, just general information on good programs out there would be helpful.
I tried gnuplot, but looking through the documentation I can't find any mention of calculating intersections, and I suspect it is not possible. Is this right?

Thanks in advance.

Dan

Not completely free, but almost so, and not completely Linux-compatible is OpenGeometry (Ordinariat für Geometrie - Universität für Angewandte Kunst).
It is not completely free: it comes as source code with a book (aka. "bookware"). And it is not completely Linux-compatible. The main version of this 3d modeling software is written for the commercial version of Visual C++ (although the 2002 edition of the book came with a Linux version, too).
A commercial version of Visual C++ is needed, because the user-inferface is based on Microsofts MFC classes that are not included in the free Visual C++ "Express" editions.

Similarly, the book "Computer Graphics and Geometric Modeling: Implementation and Algorithms" by Max K. Agoston (Springer, 2005) includes the source code of modeling software written in C++. Like OpenGeometry it is written in Visual C++ with a GUI that is, unfortunately, based on Microsoft's commercial MFC classes.

The software for the book "Geometric Algebra" (by Doorst, Fontijne, Mann) is freely available on the web (Geometric Algebra For Computer Science), though I'm not sure about the software requirements. It seems that it runs on OS/X, and Solaris, too. So, maybe, it will run on Linux. But don't take my word for it.

There is also software that might do the trick for you, that is not strictly for geometric modeling, but for making 3d drawings, such as ePiX (ePiX Home Page). This software is completely free and Linux-compatible. It is typically used to create 2d or 3d drawings for inclusion in LaTeX documents.
Another program of this sort is Asymptote (Asymptote).

Thanks very much for the suggestions, I will have a look at all those.

For not too complex problems you can also try this: Plot Graphs . It is online although linux compatible...