Stress Scalar Factor


Is it possible to multiply stress results by a scalar factor ?
If yes, how to do it ?
My stress calculation code (linear elasticity) :

with TaskManager():
EFstress = MatrixValued(H1(mesh,order=3), symmetric=True)
VMstress = GridFunction(EFstress)
VMstress.Interpolate (Stress(Sym(Grad(gfu))))


Oh right, i found just after posting this.
For those who are intersted about this topic,
the solution : VMstress.Interpolate (Stress(Sym(Grad(gfu)))*ScalarFactor)