function [x , f] = mhifft(k,ft,rflag)
% Fast Fourier INVERSE Transform of the pair (k,ft) into (x,f). The length of
% x and f must be an even number, preferably a power of two.
% x starts with zero.
% If rflag is set then only the real part of f is returned.
N = max(size(k));
x = x_of_k(k);
Period = N*(x(2)-x(1));
inull = N/2;
f = (N/Period)*ifft(circshift(ft,-[0 inull-1]));
if (nargin == 3)
if (rflag == '1')
f = real(f);
end
end