Assumptions for integration (integrate over area)

[Yuxiang Wang]

Hi all,

Not sure if sympy can do this, but wondering...

I am integrating some quantities over area in Y-Z domain. In general, most part of the integrand is constant across the area. However, there sometimes are factors such as y, z, y**2, z**2. I would like to simply denote them as:

Integration of y over area A = first moment of area of y = A_y

Integration of z over area A = first moment of area of z = A_z

Integration of y**2 over area A = second moment of area of y = I_yy

Integration of z**2 over area A = second moment of area of z = I_zz

So what I was hoping for is that I can somehow tell the system that integrate(y, some_area) == A_y, and then when it evaluates it we will plug in A_y automatically. Would that be possible?

Thank you,

Shawn