Graphing software for maths...not excel

[gam3r]

I'm looking for free graphing software which allows you to input equations and perform various mathematical calculations to them e.g

fixed point iteration, newton raphson, decimal search.

Does such exist? There is autograph 3 buy you have to pay for it.

Thank you

 

[M0KUJ1N]

R and octave spring to mind, R is more stats-oriented and octave is essentially a
matlab clone. Other (non-free) alternatives would be things like Minitab, Sigmaplot, Origin or Maple