paint a smiley face in matlab

To paint a smiley face in Matlab, we can use the rectangle and circle functions to draw the different components of the face, such as the head, eyes, and mouth. Here's some example code to create a smiley face:

main.m
% Set up the figure
figure
axis equal
axis([-1 1 -1 1])
axis off

% Draw the head
rectangle('Position',[-0.8 -0.8 1.6 1.6],'Curvature',[1 1],'FaceColor',[1 1 0],'EdgeColor','none')

% Draw the eyes
circle('Position',[-0.4 0],'Radius',0.2,'FaceColor','k')
circle('Position',[0.4 0],'Radius',0.2,'FaceColor','k')

% Draw the mouth
theta = linspace(0,pi,100);
x = 0.6*cos(theta);
y = -0.3*sin(theta)-0.2;
patch(x,y,[1 0 0],'EdgeColor','none')
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This code creates a 1.6 by 1.6 unit square in the center of the figure and sets its curvature to draw a circle. It then draws two smaller circles for the eyes with black color. Finally, it draws the mouth with a red color using the patch function to fill the area under a semi-circle with specific values of x and y. The result should be a simple, happy smiley face!