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mathplotcurvesageelliptic-curve

Sage Math elliptic curve with singularity points

I am new in sage and I have a problem. I am trying to plot the curve f(x,y)=y^2 - x^2*(x+3), but it never works. Can somebody help ?

I tried this:

sage: E = EllipticCurve([0,3,0,0,0]);
sage: E;

and it gives the error ArithmeticError: invariants (0, 3, 0, 0, 0) define a singular curve.

Solution

  • You need to do an implicit plot.

    f(x,y)=y^2 - x^2*(x+3)
implicit_plot(f,(x,-3,3),(y,-3,3))

    Looks singular to me! That would explain your error, probably EllipticCurve only will work with nonsingular curves.