Q:

Recommended (free) software to plot points in 3d

I am looking for (preferably free) software to:
1) plot 3d points read from a file. A scatter plot would be fine.
2) Optionally color the points by a property - also read from the file  
It would be terrific if this program could also compute and display the best fit plane through these points.

A:

There are quite a number of freewares which do that.

Gnuplot, with a very interesting not so frequently asked questions here (archive version), fit is easily obtained. Nice outputs to PDF and LaTeX
Matplotlib: requires Python, so that's probably not your best option if you need to produce graphs quickly, but if you are thinking about a long term solution, I would go for this one,
R, normally for statistical computations, but quite nice plotting possibilities. Also, it is a software which is intended to read data in files, so it has very powerful and easy to use functions to import CSV files and the likes,
Octave not a big fan. Don't know the new major release, though. Previous releases were based on Gnuplot for the graphic part,
Scilab has continuously grown througout the years, so as to become a monster now. Not a big fan either.

Hope you'll find your best choice here !!!
Good luck,
Sébastien

A:

I checked all of the above options out and if you want to plot something in 3D in the next ten minutes, and not ten days from now, check out Graphing Calculator 3D.

A:

Asymptote vector graphics language. Check out the gallery of graphs/plots/sketches. Here is very pretty examples/code page from France.

