clc
clear
xdel(winsid())
format(25)

function y = f(x)
    y = x.^4
endfunction

n = 5
old = 'f';
for i=1:n
    new = 'd'+string(i)+'f';
    deff('y='+new+'(x)','y=numderivative('+old+',x)');
    old=new;
end

