Python identity Examples

Example #1

def A11(w):
    u = w["disp"]
    p = w["press"]
    eye = identity(u)
    F = grad(u) + eye
    J = det(F)
    Finv = inv(F)
    L = (p * J * np.einsum("lk...,ji...->ijkl...", Finv, Finv)
         - p * J * np.einsum("jk...,li...->ijkl...", Finv, Finv)
         + mu * np.einsum("ik...,jl...->ijkl...", eye, eye))
    return L

Example #2

def deformation_gradient(w):
    dudX = grad(w["displacement"])
    F = dudX + identity(dudX)
    return F, inv(F)