How to plot the graph of the function $Re(η(s))$

The Dirichlet $\eta$ function (the alternating zeta function) is given by

$$η(s)=\sum_{n=1}^{∞}(-1)^{n-1}/n^s$$

for $s=x+iy$. I want to plot the graph of the function $Re(η(s))$ (in a specific range of $x$ and $y$) the real part of the function $η(s)$. I am searching for a software or a program available in the net to do this.

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Did you try the WolframAlpha or Mathematica programm ? –  Mher Mar 8 '14 at 16:38
@MherSafaryan: Ok I will try now. –  DER Mar 8 '14 at 16:39
I've got the graph on $[0,1]^2$, just type this in the text box of the site "Plot3D[Re[eta(x+I*y)] ,{x,0,1},{y,0,1}]" –  Mher Mar 8 '14 at 16:49
@MherSafaryan: Thank you very much. –  DER Mar 8 '14 at 17:05
You're welcome. –  Mher Mar 8 '14 at 17:23