How can I easily mark data points in a plot?

I would like to mark significant data points in a plot with an asterisk.

Is there an easy way to do that or do I have to use "text()" and manually shift the asterisk to a position next to the data point?

[Sara]

Can't you just replot them? You can use

hold on
plot(x,y,'*')

where x,y are ONLY the significant points.

Answer 1

[Chad Greene]

Sara's solution seems valid, as does your suggestion of text. Consider also annotation or label.