triqs.experimental.utility.utility.root_finder

triqs.experimental.utility.utility.root_finder()

Dispatched C++ function(s).

[1] (method: str,
     f: (float) -> float,
     x_init: float,
     y_value: float,
     precision: float,
     delta_x: float,
     max_loops: int = 1000,
     x_name: str = "",
     y_name: str = "",
     verbosity: bool = False)
  -> tuple[float, float]

Find the value \(x\) that solves \(f(x) = y\) using the requested root-finding method.

This is the main entry point of the root finder. It first brackets the solution and then refines it with either a dichotomy or a bisection step, depending on the chosen method.

It raises an error if the method name is not recognized.

Parameters:

methodstr

Root-finding method, either “dichotomy” or “bisection”.

f(float) -> float

Function \(f(x) : \mathbb{R} \to \mathbb{R}\) whose root is sought.

x_initfloat

Initial guess for \(x\).

y_valuefloat

Target value \(y\) for \(f(x)\).

precisionfloat

Absolute precision \(|f(x) - y|\) at which the iteration stops.

delta_xfloat

Step size used when bracketing the solution.

max_loopsint

Maximum number of iterations.

x_namestr

Name of the \(x\) variable, used in the progress log.

y_namestr

Name of the \(y = f(x)\) variable, used in the progress log.

verbositybool

Whether to print the convergence progress.

Returns:

tuple[float, float]

Pair \((x, f(x))\) with \(f(x) = y\) within the requested precision.