NewtonAlgorithm

NewtonAlgorithm(initial: bool = False, initial_then_current: bool = False)

Bases: Algorithm

Newton-Raphson nonlinear solution algorithm.

NewtonAlgorithm uses the classical Newton-Raphson iteration scheme to solve nonlinear equilibrium residual equations. It reforms the tangent stiffness matrix at every iteration.

Tcl form

algorithm Newton [-initial] [-initialThenCurrent]

Example

from femora.core.model import Model

model = Model()
algo = model.analysis.algorithm.newton(initial_then_current=True)

Create a Newton-Raphson solution algorithm.

Parameters:

Name	Type	Description	Default
`initial`	`bool`	If True, uses the initial stiffness matrix throughout the iterations.	`False`
`initial_then_current`	`bool`	If True, uses initial stiffness for the first iteration, and then reforms the tangent stiffness for subsequent iterations.	`False`

Raises:

Type	Description
`ValueError`	If both initial and initial_then_current are set to True.