ahmet / Python-for-Data-Science

from typing import Any


def ft_mean(values: list) -> float:
    """Return the mean of a non empty list of numbers."""
    return sum(values) / len(values)


def ft_median(values: list) -> float:
    """Return the median of a non empty list of numbers."""
    ordered = sorted(values)
    middle = len(ordered) // 2
    if len(ordered) % 2:
        return ordered[middle]
    return (ordered[middle - 1] + ordered[middle]) / 2


def ft_percentile(values: list, percent: float) -> float:
    """Return a percentile, between 0 and 1, by linear interpolation."""
    ordered = sorted(values)
    position = percent * (len(ordered) - 1)
    lower = int(position)
    upper = min(lower + 1, len(ordered) - 1)
    weight = position - lower
    return float(ordered[lower] + (ordered[upper] - ordered[lower]) * weight)


def ft_quartile(values: list) -> list:
    """Return the 25% and 75% quartiles of a list of numbers."""
    return [ft_percentile(values, 0.25), ft_percentile(values, 0.75)]


def ft_var(values: list) -> float:
    """Return the variance of a non empty list of numbers."""
    mean = ft_mean(values)
    return sum((value - mean) ** 2 for value in values) / len(values)


def ft_std(values: list) -> float:
    """Return the standard deviation of a non empty list of numbers."""
    return ft_var(values) ** 0.5


def ft_statistics(*args: Any, **kwargs: Any) -> None:
    """Print the statistics of args asked by the values of kwargs.

    An unknown operation is ignored, a computation that cannot be
    done prints ERROR.
    """
    operations = {
        "mean": ft_mean,
        "median": ft_median,
        "quartile": ft_quartile,
        "std": ft_std,
        "var": ft_var,
    }
    for wanted in kwargs.values():
        if wanted not in operations:
            continue
        try:
            print(f"{wanted} : {operations[wanted](list(args))}")
        except Exception:
            print("ERROR")


def main() -> None:
    """Test the statistics on several sets of arguments."""
    ft_statistics(1, 42, 360, 11, 64,
                  toto="mean", tutu="median", tata="quartile")
    print("-----")
    ft_statistics(5, 75, 450, 18, 597, 27474, 48575,
                  hello="std", world="var")
    print("-----")
    ft_statistics(5, 75, 450, 18, 597, 27474, 48575,
                  ejfhhe="heheh", ejdjdejn="kdekem")
    print("-----")
    ft_statistics(toto="mean", tutu="median", tata="quartile")
    print("-----")
    ft_statistics("a", "b", toto="mean", tutu="std")


if __name__ == "__main__":
    main()