On 27.04.2013 14:48, Gallego Samy wrote:
> Hello,
>
> I would like to plot complex roots of polynomials, I have tried this:
> ------
> a:allroots(x^3+3*x^2+x+1,x);
> plot2d([['discrete, realpart(a), imagpart(a)]], [x,-5,5]);
> ------
> but maxima is not happy because "allroots" output is of the form
> [x=...., x=....,x=] and "plot2d" would like a list of complex (without
> "x=").
>
> Thanks in advance for your help,
>
> Samy
>
>
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>
/* remove "z=" from list a */
a:map('rhs,a);
a:map('rectform,a);
a:map('float,a);
draw2d(
point_type = filled_circle,
points_joined = false,
point_size = 0.7,
point_size = 1.2,
key= "critical points",
color = blue,
points(map(realpart,a),map(imagpart,a))
);
HTH
Adam
http://commons.wikimedia.org/wiki/Category:Images_with_Maxima_CAS_source_code