Merged in feature/dataspline (pull request #14) Feature/dataspline Approved-by: Jonatan Werpers <jonatan.werpers@it.uu.se> Approved-by: Martin Almquist <malmquist@stanford.edu>

function plotf(f,a,b,opt)
    if ~exist('opt')
        opt = '';
    end

    x = linspace(a,b);
    for i = 1:length(x)
        y(i) = f(x(i));
    end
    plot(x,y,opt)
end