# Celebrating Spring: MATLAB Tulip

Joining us again is Eric Ludlam, development manager of MATLAB’s charting team. Discover more about Eric on our contributors bio page. Last time Eric was here, Daffodils were on his mind. Now, he focuses on tulips.
Spring is here in Natick and the tulips are blooming! While tulips appear only briefly here in Massachusetts, they provide a lot of bright and diverse colors and shapes. To celebrate this cheerful flower, here's some code to create your own tulip!
This script uses some fun tricks, like extracting a subset of the 'hot' colormap for a red-to-yellow colormap, and specifying several material properties to give it a more sunny day look. There's also the sinpi and cospi functions that Mike likes so much!
Explore the code and create some new breeds of tulips for your MATLAB.
%% MATLAB Tulip
np = 3; % number of petals
n=np*20+1; % Theta resolution
theta=linspace(0, np*(1/np)*2,n);
r=linspace(0,1,80)';
newplot
for k=[0 1/np] % 2 layers of petals
x=1-(.8*(1-mod(np*(theta+k),2)).^3-.05).^2/2;
Z1=((x.*r).^6);
R2=x.*r*(1-k*.38);
R3=x.*(r.^8)*.4.*Z1;
X=R2.*cospi(theta)-R3.*cospi(theta);
Y=R2.*sinpi(theta)-R3.*sinpi(theta);
C=repmat(r,1,n).^25;
%% Petals
surface(X,Y,Z1*2,C,FaceColor="interp",EdgeColor="none",FaceLighting="gouraud");
line(X(end,:),Y(end,:),Z1(end,:)*2,Color="#cc0",LineWidth=1);
end
%% Stem
[CX,CY,CZ]=cylinder;
surface(CX*.1,CY*.1,(CZ-1)*2,[],FaceColor="#9b8",EdgeColor="none");
%% Decorate!
cmap=hot(200); % Colors of tulip
colormap(cmap(80:150,:)) % Extract subset of hot colormap.
axis off equal
view([0,10]);
material([.6 .9 .3 2 .5])
camlight(40,40)

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