Python Simple Programs

check_if_a_number_is_odd_or_even.py

# Python program to check if the input number is odd or even.
# A number is even if division by 2 gives a remainder of 0.
# If the remainder is 1, it is an odd number.

num = int(input("Enter a number: "))
if (num % 2) == 0:
   print("{0} is Even".format(num))
else:
   print("{0} is Odd".format(num))

check_whether_a_string_is_palindrome_or_not.py

# Program to check if a string is palindrome or not

my_str = 'aIbohPhoBiA'

# make it suitable for caseless comparison
my_str = my_str.casefold()

# reverse the string
rev_str = reversed(my_str)

# check if the string is equal to its reverse
if list(my_str) == list(rev_str):
   print("The string is a palindrome.")
else:
   print("The string is not a palindrome.")

simple_calculator.py

# Program make a simple calculator

# This function adds two numbers
def add(x, y):
    return x + y

# This function subtracts two numbers
def subtract(x, y):
    return x - y

# This function multiplies two numbers
def multiply(x, y):
    return x * y

# This function divides two numbers
def divide(x, y):
    return x / y


print("Select operation.")
print("1.Add")
print("2.Subtract")
print("3.Multiply")
print("4.Divide")

while True:
    # take input from the user
    choice = input("Enter choice(1/2/3/4): ")

    # check if choice is one of the four options
    if choice in ('1', '2', '3', '4'):
        num1 = float(input("Enter first number: "))
        num2 = float(input("Enter second number: "))

        if choice == '1':
            print(num1, "+", num2, "=", add(num1, num2))

        elif choice == '2':
            print(num1, "-", num2, "=", subtract(num1, num2))

        elif choice == '3':
            print(num1, "*", num2, "=", multiply(num1, num2))

        elif choice == '4':
            print(num1, "/", num2, "=", divide(num1, num2))
        
        # check if user wants another calculation
        # break the while loop if answer is no
        next_calculation = input("Let's do next calculation? (yes/no): ")
        if next_calculation == "no":
          break
    
    else:
        print("Invalid Input")

weight_converter.py

WEIGHT_CONVERSIONS = {
    "kg": 2.20462,
    "lb": 0.453592,
    "g": 0.00220462,
    "oz": 0.0283495,
    "mg": 0.00000220462,
}


def convert_weight(weight, unit_from, unit_to):
    if unit_from == unit_to:
        return weight
    return weight * WEIGHT_CONVERSIONS[unit_from] / WEIGHT_CONVERSIONS[unit_to]


def get_unit_input(msg):
    while True:
        unit = input(msg)
        if unit in WEIGHT_CONVERSIONS:
            break
        print("Invalid unit, valid units are: {}".format(
            ", ".join(WEIGHT_CONVERSIONS.keys())))
    return unit


def main():
    weight = float(input("Please enter the weight: "))

    unit_from = get_unit_input("Please enter the unit of the weight: ")
    unit_to = get_unit_input("Please enter the unit to convert to: ")

    converted_weight = convert_weight(weight, unit_from, unit_to)
    print(f"{weight} {unit_from} is {converted_weight} {unit_to}")


main()