nlsq.core.functions.polynomial

nlsq.core.functions.polynomial(degree)

Create polynomial function of given degree.

Returns a function that computes: y = c0*x^n + c1*x^(n-1) + … + cn where n is the degree.

Parameters:

degree (int) – Polynomial degree (0, 1, 2, 3, …)

Returns:

poly_func – Polynomial function with signature poly(x, *coeffs)

Return type:

callable

Examples

>>> from nlsq import curve_fit
>>> from nlsq.core.functions import polynomial
>>> import numpy as np
>>>
>>> # Fit quadratic: y = ax² + bx + c
>>> quadratic = polynomial(2)
>>> x = np.linspace(-5, 5, 50)
>>> y = 2*x**2 + 3*x + 1 + np.random.normal(0, 0.5, 50)
>>> popt, pcov = curve_fit(quadratic, x, y, p0='auto')
>>> print(f"Coefficients: {popt}")