MATLAB: Plot vertical lines from a point to x-axis

plotting

I would like to plot veritcal lines in the xy-plane, from a given point down to the x-axis.

I have looked around, but I can find anything that solves my problem.

Use a stem plot.

hold on;
plot([x x], ylim)

Or better yet, in case you have multiple sets of axes:

% if ax is the set of axes you are plotting to
hold(ax, 'on');
plot(ax, [x x], ylim(ax))

plot(1:10)
set(gca,'XAxisLocation','top')