Some questions about SAGE I search a programmable calculator like PARI/GP. In the net, I came across
 SAGE. I have some questions about the download of SAGE


*

*Is it really absolutely free ?

*Is it faster than PARI/PG ?

*Has it more features (for example galois groups of polynomials of high
degrees) ?

*Which space is needed on disk ?

*Does it have tar.gz-files or zip.files. In the first case, I do not have
the supporting programs. The best case would be : .exe (executable)
Perhaps, someone has SAGE and can answer my questions .
 A: *

*Yes, it is totally free. No ads, no paying for extra bits, nothing like that. It's open source, even, so you can download all the source code you would ever want. (They even encourage you too, and improve it along the way).

*Is it faster than PARI - in short, no. PARI is actually included inside SAGE (along with many other free things like maxima, etc.). SAGE interfaces to PARI, and this comes at a cost. But SAGE gets to use the same optimized algorithms as PARI, and I've never noticed  that any difference in speed is noticeable.

*It has many features, and these features are expanding. It can do many things with Galois groups, but I have not played much with these.

*SAGE is huge because it's designed to be completely self-sufficient. Thus it includes many packages that a competent computer-using mathematician already has, and takes up roughly 4 gigs on file (their site says 7 gigs are necessary to run it). There are really two options here: someone can run a sage server and you can access it, so that it takes up zero space on disk but someone has to have a dedicated server; or you can have all 4 gigs on your own disk. If this is the case, you'll actually need to run it on linux. If you have Windows/Mac, they provide a virtual image already installed on a red hat emulator that can be used with other (also free) software like virtualbox.

*Since you run Windows, you won't be getting either a tar.gz or a zip, but rather a .ova file that can be used in virtualbox (which runs on Windows via an .exe). On their site, they link you to virtualbox too.
If you just want to try it out, you can try their free notebook, but it's pretty slow because anyone can use it (and many do). Of course, if you want to try it out, just go ahead and download it and install it. It does not take very long, and their documentation for installation is pretty good.
As a disclaimer, I am a SAGE developer as well (in the contributing to their code through their trac server because it's open source sense, not in the I-helped-design-and-come-up-with-the-idea sense).
