def calculate_axial_from_stress(self, R, J):
"""
Calculate the axial force by integrating sigma_zz over the area
Parameters:
R final residual
J final jacobian
"""
#pylint: disable=no-value-for-parameter, invalid-unary-operand-type
if self.state_np1.ndim == 1:
dx = self.state_np1.basis.interpolate(
self.state_np1.mesh.p[0]
)[0][0] * self.state_np1.basis.dx * 2.0 * np.pi
else:
dx = self.state_np1.basis.dx
fake_force = self._internal_force(self.state_np1.tangent[:, :, 2, 2])
de = utils.solve(*utils.condense(J, fake_force, D=self.edofs),
solver=utils.solver_direct_scipy())
fake_strain = self.calculate_strain(de)
integrand1 = np.einsum('iijk',
self.state_np1.tangent[2, 2] * fake_strain)
integrand2 = self.state_np1.tangent[2, 2, 2, 2]
self.state_np1.force = np.sum(self.state_np1.stress[2, 2] * dx)
self.state_np1.stiffness = np.sum(
(-integrand1 + integrand2) * dx) / self.state_np1.h
def linear_solve(self, J, R):
"""
Do the linear solve for a particular jacobian and residual
Parameters:
J Jacobian sparse matrix
R residual vector
"""
#pylint: disable=no-value-for-parameter
return utils.solve(*utils.condense(J, R, D=self.edofs),
solver=utils.solver_direct_scipy())