how can I make a colored 2D-surface in a polar plot? I want to give some labels to this polar... It is possible?

clc

c=input('How many blades are there in the blower?:');

t = 0:.01:2*pi;

if mod(c,2)==1 polar(t,(cos((c*t))),'-r') else polar(t,(cos((c/2)*t).^2),'-r') end

% find all of the text objects in the polar plot

h = findall(gcf,'type','text');

% delete the text objects

delete(h);

Answer 1

[Joseph Cheng]

the fill is a bit temperamental (does not work for odd blades). but it should be a starting point for you to look further.

clc
% c=input('How many blades are there in the blower?:');
c=randi(6,1,1);
t = 0:.01:2*pi;
if mod(c,2)==1 
    ph = polar(t,(cos((c*t))),'-r') 
else
    ph = polar(t,(cos((c/2)*t).^2),'-r') 
end
% find all of the text objects in the polar plot
h = findall(gcf,'type','text');
% delete the text objects
delete(h);
patch(get(ph,'XData'), get(ph,'YData'), 'g')

fins = linspace(0,360,c+1);
for ind = 1:c
    txtx = 1.2*cosd(fins(ind));
    txty = 1.2*sind(fins(ind));
    text(txtx,txty,['fin ' num2str(ind)])
end

[Marcos Perez]

nice!!

Answer 2

[bio lim]

clc

c=input('How many blades are there in the blower?:');

t = 0:.01:2*pi;

if mod(c,2)==1 
  radius = cos(c*t);
  radius(radius <= 0) = 0;
  ph = polar(t,(radius),'-r') 
else
  ph = polar(t,(cos((c/2)*t).^2),'-r')
end

% find all of the text objects in the polar plot

h = findall(gcf,'type','text');

% delete the text objects

delete(h);
patch(get(ph,'XData'), get(ph, 'YData'), 'b')

The rest is the code from Cheng, except the 'fins' was renamed to 'Blade' as the image suggested.

fins = linspace(0,360,c+1);

for ind = 1:c
  txtx = 1.2 * cosd(fins(ind));
  txty = 1.2 * sind(fins(ind));
  text(txtx,txty,['Blade ' num2str(ind)])
end