function f = kaczmarz(f, p, W)

    n_mesures = size(p, 1);

    W = W';
    norm_W = sum(W.^2, 1);

    for i = 1:n_mesures

        Wi = W(:,i)';
        norm_Wi = norm_W(i);

        if norm_Wi > 0
            f = f + (p(i) - Wi * f) / norm_Wi * Wi';
        end
    end
end