How can I do an elliptic curve in Matlab?

How can I do an elliptic curve in Matlab for the following function ' y^2-y=x^3-x ' ?

Answer 1

[Alan Stevens]

Here's one simple way:

% y^2 - y = x^3 - x
% y = (1 +/- sqrt(4x^3 - 4x + 1))/2

n = 1000;
x = -2:1/n:2;

d = sqrt(4*x.^3-4*x+1);
id = find(d~=real(d));
d(id) = nan;
y1 = (1 + d)/2;
y2 = (1 - d)/2;

plot(x,y1,'r',x,y2,'r')