function bday(age)

t =  [1:21 21 + (1:age-21)*i]


stem3( real(t), imag(t), real(t) + imag(t) )
hold on
plot3( real(t), imag(t), real(t) + imag(t), 'k' )
hold off

set( gca, 'xtick', [0:5:15 21], 'xticklabel', '0|5|10|15|21', 'Box', 'off' )
view( -50, 30 )

title( 'Age Progression in Humanoids', 'FontSize', 16 )
xlabel( 'real' )
ylabel( 'imaginary' );
zlabel( 'actual' )