exp(tdddx)f(x)=f(x+t) exp(td\frac{d}{dx})f(x)=f(x+t) exp(tddxd)f(x)=f(x+t)
exp(t1∂∂x+t2∂∂y)f(x,y)=f(x+t1,y+t2) exp(t_1\frac{\partial}{\partial x}+t_2\frac{\partial}{\partial y})f(x,y)=f(x+t_1,y+t_2) exp(t1∂x∂+t2∂y∂)f(x,y)=f(x+t1,y+t2)
