First of all Octave is a MatLab clone, so yes you can most certainly use it without needing Matlab. (in fact it can be used as a drop in replacement for Matlab, and matlab code will usually run fine in octave).
Secondly, the octave web page is here
, and you can go to the download page and download the source package. But it is available as a package for Fedora. see https://admin.fedoraproject.org/pkgd...29bf9127bbd1ce
There is also a package called QtOctave, which provides a workspace somewhat similar to the the Matlab GUI, if you so desire. (Admittedly it isn't quite as nice as Matlab, but considering the difference in price I think it's pretty good.)