Paragon math - hypotenuse

I'm trying to get a LPYR of a component to have a length equal to the hypotenuse of values given as DESPRAMs.  

Formula:  SQRT (A^2 + B^2)

For this piece: A=B= RPRO LGTH

I've tried SQRT (2 * (RPRO LGTH) EXP 2) as well as some other variations with no luck.

I'm trying to get a LPYR of a component to have a length equal to the hypotenuse of values given as DESPRAMs.  

Formula:  SQRT (A^2 + B^2)

For this piece: A=B= RPRO LGTH

I've tried SQRT (2 * (RPRO LGTH) EXP 2) as well as some other variations with no luck.