Struct newton_rootfinder::iteratives::IterativeParamsFD

pub struct IterativeParamsFD { /* fields omitted */ }

Extension of iteratives. FD stands for Finite-Difference

In addition to the already defined parameters of an iteratives, The fact that the jacobian is going to be evaluated with finite-differences leads to the necessity to parametrize the way the perturbation on the iteratives are made.

This functionality is provided thourgh the compute_perturbation() method of the Iterative trait

Implementations

impl IterativeParamsFD

pub fn new(
    max_step_abs: f64,
    max_step_rel: f64,
    min_value: f64,
    max_value: f64,
    dx_abs: f64,
    dx_rel: f64,
    perturbation_method: PerturbationMethod
) -> Self

pub fn get_min_value(&self) -> f64

pub fn get_max_value(&self) -> f64

pub fn get_max_step_abs(&self) -> f64

pub fn get_max_step_rel(&self) -> f64

pub fn get_dx_abs(&self) -> f64

pub fn get_dx_rel(&self) -> f64

pub fn get_perturbation_method(&self) -> PerturbationMethod

pub fn get_iterative_params(&self) -> &IterativeParams

pub fn extend(
    iterative_params: IterativeParams,
    dx_abs: f64,
    dx_rel: f64,
    perturbation_method: PerturbationMethod
) -> Self

Transform a IterativeParms and extend it into a IterativeParamsFD

Trait Implementations

impl Clone for IterativeParamsFD

fn clone(&self) -> IterativeParamsFD

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for IterativeParamsFD

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for IterativeParamsFD

fn default() -> IterativeParamsFD

Returns the “default value” for a type.

impl Display for IterativeParamsFD

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Iterative for IterativeParamsFD

fn step_limitation(&self, value_current: f64, value_next: f64) -> f64

Compute a limited update step

This method points is a wrapper around the method of IterativeParams. Check its documentation for more details

fn compute_perturbation(&self, x: f64) -> f64

Compute the perturbation for finite differences evaluation.

For a given f(x), this method compute the dx to use in the formula:

 df/dx = (f(x+dx)-f(x))/dx

The parametrization here defines dx with regards to :

• dx_abs: the absolute perturbation step
• dx_rel: the relative perturbation step

For each case we would have :

• dx = dx_abs
• dx = dx_rel*abs(x)

The implementation here allows you to choose and combine the formulas:

• dx = max(dx_abs, dx_rel*abs(x))
• dx = dx_abs + dx_rel*abs(x)

This is achieved through the perturbation_method field.

It is also possible to get one of the two basic cases by setting the other to 0:

• dx_abs = 0 implies dx = dx_rel*abs(x)
• dx_rel = 0 implies dx = dx_abs

fn with_finite_diff(&self) -> bool

Method to differente without panicking if it is working with finite differences

impl PartialEq<IterativeParamsFD> for IterativeParamsFD

fn eq(&self, other: &IterativeParamsFD) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &IterativeParamsFD) -> bool

This method tests for !=.

impl StructuralPartialEq for IterativeParamsFD