BMI_Calculator.py

"""
The following application calculates
    - BMI,
    - Ideal Weight and
    - Amount of extra weight
from a person's weight and height.
"""


# convert meter to inch
def to_inches(meter):
    return round(meter * 39.37)


# Ideal Weight Calculation, D. R. Miller Formula (1983)
def cal_ideal_weight(meter):
    inches = to_inches(meter)
    is_male = input("Gender (M/F) -  ") == "M"
    if is_male:
        # Male: 56.2 kg + 1.41 kg per inch over 5 feet
        result = (1.41 * (inches - 60)) + 56.2
    else:
        # Female: 53.1 kg + 1.36 kg per inch over 5 feet
        result = (1.36 * (inches - 60)) + 53.1
    return round(result)


# BMI Calculation, BMI = weight(kg) / height^2 (m)
def cal_bmi(weight, height):
    # BMI formula
    result = weight / height ** 2
    return round(result)


def display_results(weight, ideal_weight, extra_weight, bmi):
    print("*** Result ***")
    print("BMI : " + str(bmi))
    print("Body Weight : " + str(weight) + "kg")
    print("Ideal Weight : " + str(ideal_weight) + "kg")
    print("Extra Weight : " + str(extra_weight) + "kg")


# main function to start the process
def main():
    # user input (height)
    height = float(input("Your height in meter - "))
    # user input (weight)
    weight = float(input("Your weight in kg - "))

    ideal_weight = cal_ideal_weight(height)
    extra_weight = weight - ideal_weight  # body weight - ideal weight
    bmi = cal_bmi(weight, height)

    # calling display function
    display_results(weight, ideal_weight, extra_weight, bmi)


# start the process
main()