function [y,no] = f1(x,ni)

x = x(:);
np = length(x);
if length(x) ~= length(ni)
    disp 'error: vectors not same length'
    return
end

y = ([x; 0;0;] + 0.5*[0;x; 0] + (0.5)^2*[0;0;x])';
no = [min(ni):min(ni)+np+1];