Beam Deflection Calculation

Here is my beam deflection calculation in LibreOffice Calc using custom function.
Using Macros, I created a function that calculates deflection for two types of beams: cantilever and simple.

Here is the function:

function DeflectionP(key,P,E,J,l,a,b)

if key="simple" then DeflectionP=P*a^2*b^2/(3*E*J*l)

if key="cantilever" then DeflectionP=P*l^3/(3*E*J)

end function