Rooftop basi functions

Hi all,

Can anyone tell me what are rooftop basis functions that are usually encountered in MoM simulations ? Some equations would be of great help Thanks.

-svarun

Hi
rooftop function are used in the MOM as weighting functions. these functions are
triangular functions.
T(x)=(x+Dx-xk)/Dx for xk-Dx/2<x<xk and
T(x)=(-x+Dx+xk)/Dx for xk-Dx/2<x<xk+Dx/2