pytongiinterpolacje

import math


def f(x):
    return x + (1 / x**2)


def interp_parabolic(_a, _b, eps):
    a = _a
    b = _b
    c = a + ((b - a) * 0.5)
    d_top = 0.0
    d_bottom = 0.0
    d = 0.0
    l = b - a

    while True:
        if l < eps:
            print('a:', a)
            print('b:', b)
            print('c:', c)
            print('d:', d)
            return True
        else:
            f_c = f(c)
            f_b = f(b)
            f_a = f(a)

            a_2 = a**2
            b_2 = b**2
            c_2 = c**2

            d_top = (f_a * (c_2 - b_2)) + \
                (f_c * (b_2 - a_2)) + (f_b * (a_2 - c_2))
            d_bottom = (f_a * (c - b)) + (f_c * (b - a)) + (f_b * (a - c))
            d = 0.5 * (d_top / d_bottom)

            f_d = f(d)

            if d < c:

                if f_d < f_c:
                    b = c
                    c = d
                else:
                    a = d

            else:
                if f_d < f_c:
                    a = c
                    c = d
                else:
                    b = d

        l = b - a


interp_parabolic(1.0, 2.0, 0.0001)