pyroots

0.5.0 verified Fri May 01 auth: no python

Pure Python single-variable function solvers. Provides root-finding algorithms such as bisection, Newton-Raphson, secant, and others. Current version: 0.5.0. Release cadence is low (last release 2021).

pip install pyroots

Common errors

error ModuleNotFoundError: No module named 'pyroots.methods' ↓

cause The submodule 'methods' was removed in version 0.5.0.

fix

Use 'from pyroots import bisection' instead.

error TypeError: only length-1 arrays can be converted to Python scalars ↓

cause Passing a numpy array or list as the function argument where a scalar is expected.

fix

Ensure your function f(x) returns a single float, not an array.

error ValueError: f(a) and f(b) must have opposite signs ↓

cause Bisection and bracket-based methods require the function to change sign over the interval.

fix

Choose an interval [a, b] such that f(a)*f(b) < 0.

Warnings

deprecated The 'methods' submodule (e.g., from pyroots.methods import bisection) is deprecated; use top-level imports (from pyroots import bisection). ↓

fix Use 'from pyroots import bisection' instead.

gotcha All solvers require a function that returns a scalar; they do not support vectorized functions or arrays. Passing a vector will fail. ↓

fix Ensure your function f(x) returns a single float, not a list or numpy array.

gotcha Flexible tolerance 'xtol' behavior: bisection uses 'xtol' as absolute tolerance; newton uses 'xtol' for step size. Inconsistent across methods – check source if expecting identical semantics. ↓

fix Read docstring of each solver to confirm tolerance behavior.

deprecated Support for Python 2.7 and 3.5 is deprecated; future releases may drop it. ↓

fix Use Python >=3.6.

Imports

bisection
```
from pyroots import bisection
```
newton
```
from pyroots import newton
```
secant
```
from pyroots import secant
```
ridders
```
from pyroots import ridders
```
brent
```
from pyroots import brent
```

Quickstart

Find a root of f(x)=x^3 - 2x -5 in interval [2,3] using bisection.

from pyroots import bisection

def f(x):
    return x**3 - 2*x - 5

root = bisection(f, 2, 3)
print(f"Root: {root:.6f}")