voltage_divider

import math
from typing import Tuple


def voltage_divider(v_input: float, v_output: float, current: float) -> Tuple[float, float, float]:
    """
    Calculate a voltage divider.

    :param v_input: Input voltage in V
    :param v_output: Output voltage in V
    :param current: defined current in A

    :returns: r1, r2, v_output
    """
    R = v_input / current
    # e24 = [round(math.pow(10 ** x, 1/24), 1) for x in range(24)]
    e24 = [
        1.0, 1.1, 1.2, 1.3, 1.5, 1.6, 1.8, 2.0,
        2.2, 2.4, 2.7, 3.0, 3.3, 3.6, 3.9, 4.3,
        4.7, 5.1, 5.6, 6.2, 6.8, 7.5, 8.2, 9.1,
    ]
    r1 = R / v_input * (v_input - v_output)
    r2 = R - r1
    factor_1 = int(math.log10(r1))
    factor_2 = int(math.log10(r2))
    rr1, rr2 = 0, 0
    for res in e24:
        if res * 10 ** factor_1 <= r1:
            rr1 = res
        if res * 10 ** factor_2 <= r2:
            rr2 = res
    idx_1 = e24.index(rr1)
    idx_2 = e24.index(rr2)
    if idx_1 < len(e24):
        idx_1 += 1
    if idx_2 < len(e24):
        idx_2 += 1
    r1 = e24[idx_1] * 10 ** factor_1
    r2 = e24[idx_2] * 10 ** factor_2
    return r1, r2, v_input - v_input / (r1 + r2) * r1