function fouriersmooth
% Fourier coefficients for a continuous function
kmax = 200;
f = zeros(kmax+1,1);
f(1) = abs(quadgk(@(x)mycos(x,0),0,2*pi));
for k = 1:kmax,
   f1 = quadgk(@(x)mysin(x,k),0,2*pi);
   f2 = quadgk(@(x)mycos(x,k),0,2*pi);
   f(k+1) = sqrt(f1^2+f2^2); 
end

subplot(1,2,1);
semilogy(0:kmax,f),
makelarge
xlabel('k');

subplot(1,2,2);
plot(100:kmax,f(101:end)),
makelarge
xlabel('k');

title('Fourier coefficients of cont. function');


function y = mysin(x,k)
y = abs(pi-x) .* sin(k*x);

function y = mycos(x,k)
y = abs(pi-x) .* cos(k*x);