Dahlia

on 12 Oct 2022

% Dahlia

% Permutation of the rose where instead of rounded

% petals, use an exponent to make rounded petals.

% This colonop will be used again for the colormap

m=0:.01:1;

[R,T]=ndgrid(m,-2:.01:20);

x=1-abs(1-mod(12.6*T,2)).^2/2;

P=pi*exp(-T/8)/2;

s=@sin;

c=@cos;

u=s(P);

v=c(P);

y=R.^2.*(1.3*R-1).^2.*u;

g=@(f)x.*(R.*u+y.*v).*f(T*pi);

X=g(s);

Y=g(c);

Z=R.*v-y.*u;

surf(X,Y,x.*Z,hypot(hypot(X,Y),Z));

shading interp

axis equal off

% Create a purply colormap

% This bit of trickery recycles 'm' from above which happened to

% be the same colonop needed for the colormap.

M(1,:)=m;

M(3,:)=m*.1+.9;

colormap(M');