[Ridvan]

Hi,
I am trying to write gravitational acceleration expression by tui but i don't exactly know how to.

From the Gui, my expression is something like

IF(t <= 3 [s], 15 [m/s^2], 0 [m/s^2])

and console says

x-component of gravity (in [m/s^2]) [((constant . 0) (expression . ""))]


How can I write if condition correctly by tui?

Thanks in advance.