'LineWidth' feature is not available in 2012a?

I have been trying to thicken my lines for a while now but it seems I have found the problem

>> help LineWidth

LineWidth not found.

Why is this not available in 2012a???

Answer 1

[Sean de Wolski]

It's a property of a line not a function:

h = plot(rand(1,10));
set(h,'LineWidth',10)

Answer 2

[Azzi Abdelmalek]

you will find it in

doc plot