A simple Python class to min-max scale sequences of numbers.

min_max_scaler.py

from typing import Tuple, List

class MinMaxScaler:
    def __init__(self, values: Tuple) -> List:
        self.values = values
        self.min_val = min(values)
        self.max_val = max(values)
        self.max_min_diff = self.max_val - self.min_val

    def min_max_scale(self, x: Tuple):
        return [(x_i - self.min_val) / self.max_min_diff for x_i in x]

    def inverse_min_max_scale(self, x: Tuple):
        return [x_i * self.max_min_diff + self.min_val for x_i in x]

if __name__ == '__main__':
    original_values = 5, 8, 12
    mms = MinMaxScaler(original_values)
    scaled_values = mms.min_max_scale(mms.values)
    scaled_values # [0.0, 0.42857142857142855, 1.0]
    mms.inverse_min_max_scale(scaled_values) # [5.0, 8.0, 12.0]