[Stephenfrazier10]

I have did this out on paper over and over, and the algorithm I have developed seems like it should work. Im not sure why its not working, any help would be appreciated.

def Binary_to_Decimal():
    Again = "Y"
    while Again in "Yy":
        binaryNumber = str(input("Enter a number in binary, to get it converted into decimal: "))
        binaryNumber = binaryNumber[::-1]
        Multiplyer = 1
        DecimalNumber = 0
        for i in range(len(binaryNumber)):
            if i == 1:
                DecimalNumber = DecimalNumber + Multiplyer
                Multiplyer = Multiplyer * 2
            elif i == 0:
                Multiplyer = Multiplyer * 2
        print("That number is decimal is: " + str(DecimalNumber))
        print("\n")
        Again = input("Do you want to convert anymore? (Y or N)")

Binary_to_Decimal()

[sepp2k]

It would help if you explained how exactly the code is not working, but at a first glance, your loop does nothing when i is neither 0 nor 1.

This post has been edited by sepp2k: 06 December 2012 - 11:35 PM

[Stephenfrazier10]

I know it assumes you enter a number in binary.

[sepp2k]

A binary number can still be more than 2 digits long.

[Tayacan]

Okay, so the problem is in your for loop. You're only doing things if i is either 1 or 0, and you're not even doing the right things in those cases. So here's what should actually happen in your for loop:

• Pull out the binary digit from the string.
  
• Multiply it with the multiplier and add it to the DecimalNumber.
  
• Double the multiplier.
  
• Proceed with the next digit.

Here's how to do that in code:

def Binary_to_Decimal():
    Again = "Y"
    while Again in "Yy":
        binaryNumber = str(input("Enter a number in binary, to get it converted into decimal: "))
        binaryNumber = binaryNumber[::-1]
        Multiplyer = 1
        DecimalNumber = 0
        for i in range(len(binaryNumber)):
            DecimalNumber += int(binaryNumber[i]) * Multiplyer # Step 1 and 2
            Multiplyer *= 2 # Step 3
        print("That number is decimal is: " + str(DecimalNumber))
        print("\n")
        Again = input("Do you want to convert anymore? (Y or N)")

Binary_to_Decimal()

[baavgai]

Look at the value in binaryNumber, not the number of i. You can actually do that with:

for i in binaryNumber:
	# do something
	if i == '1':
		# do something

Also, there is a fundamental logic error: shift then add. Reversing is wrong with that approach. Walk it:

s = '1011'
n = 0
n = n * 2 + 1 = 1
n = n * 2 + 0 = 2
n = n * 2 + 1 = 5
n = n * 2 + 1 = 11

[Stephenfrazier10]

Thanks for all your help.

[Stephenfrazier10]

I got my entire program working now!

"""
Gives the user multiple choices on converting between different number systems
used in computer science/programming
"""

def Decimal_To_Binary_Converter():
    """
    Takes a decimal base number and converts it to a binary base number
    """
    Again = "Y"
    while Again in "Yy":
        DecimalNumber = int(input("Enter a number in decimal, to get it converted into binary: "))
        BinaryVersion = int(bin(DecimalNumber)[2:])
        print("That decimal number in binary is: " + str(BinaryVersion))
        print("\n")
        Again = input("Do you want to convert anymore? (Y or N) ")
        print("\n")


def Binary_to_Decimal_Converter():
    """
    Takes a binary base number and converts it to a decimal base number
    """
    Again = "Y"
    while Again in "Yy":
        binaryNumber = str(input("Enter a number in binary, to get it converted into decimal: "))
        binaryNumber = binaryNumber[::-1]
        Multiplyer = 1
        DecimalNumber = 0
        for i in range(len(binaryNumber)):
            DecimalNumber += int(binaryNumber[i]) * Multiplyer
            Multiplyer = Multiplyer * 2
        print("That binary number in decimal is: " + str(DecimalNumber))
        print("\n")
        Again = input("Do you want to convert anymore? (Y or N) ")
        print("\n")
        

def Decimal_to_Hex_Converter():
    """
    Converts a decimal base number to a hexadecimal base number
    """
    Again = "Y"
    while Again in "Yy":
        DecimalNumber = int(input("Enter a number in decimal, to have it converted into hexadecimal: "))
        HexNum = hex(DecimalNumber)
        RealHexNum = HexNum[2:]
        print("That decimal number in hexadecimal is: " + str(RealHexNum))
        print("\n")
        Again = input("Do you want to convert anymore? (Y or N) ")
        print("\n")


def Binary_to_Hex_Converter():
    """
    Converts a binary base number to a hexadecimal base number
    """
    Again = "Y"
    while Again in "Yy":
        BinaryNumber = str(input("Enter a number in binary, to have it converted to hexadecimal: "))
        BinaryNumber = BinaryNumber[::-1]
        Multiplyer = 1
        DecimalNumber = 0
        for i in range(len(BinaryNumber)):
            DecimalNumber += int(BinaryNumber[i]) * Multiplyer
            Multiplyer = Multiplyer * 2
        hexVersion = hex(DecimalNumber)
        hexVersion = hexVersion[2:]
        print("That binary number in hexadecimal is " + str(hexVersion))
        print("\n")
        Again = input("Do you want to convert anymore? (Y or N) ")
        print("\n")


def Hex_to_Decimal_Converter():
    """
    Converts a hexadecimal base number to a decimal base number
    """
    Again = "Y"
    while Again in "Yy":
        HexValue = input("Enter a number in hexadecimal, to get it converted into decimal: ")
        DecimalValue = int(HexValue, 16)
        print("That hexadecimal number in decimal is " + str(DecimalValue))
        print("\n")
        Again = input("Do you want to convert anymore? (Y or N) ")
        print("\n")
        

def Hex_to_Binary_Converter():
    """
    Converts a hexadecimal base number to a binary base number
    """
    Again = "Y"
    while Again in "Yy":
        HexValue = input("Enter a number in hexadecimal, to get it converted into binary: ")
        DecimalValue = int(HexValue, 16)
        BinaryValue = bin(DecimalValue)
        BinaryValue = BinaryValue[2:]
        print("That hexadecimal number in binary is " + str(BinaryValue))
        print("\n")
        Again = input("Do you want to convert anymore? (Y or N) ")
        print("\n")
        
            
def main():
    """
    Asks the user which type of conversion they want done, then takes their choice and
    calls on the appropriate function. Prevents the user from picking an option that is
    not a choice with an else statement.
    """
    print("Welcome to my Binary and Decimal Converter!")
    print("------------------------------------------------")
    print("Press 1 for decimal to binary ")
    print("Press 2 for binary to decimal")
    print("Press 3 for decimal to hexadecimal")
    print("Press 4 for binary to hexadecimal")
    print("Press 5 for hexadecimal to decimal")
    print("Press 6 for hexadecimal to binary")
    print("\n")
    choice = input("What do you want to do? ")
    if choice == "1":
        print("\n")
        Decimal_To_Binary_Converter()
    elif choice == "2":
        print("\n")
        Binary_to_Decimal_Converter()
    elif choice == "3":
        print("\n")
        Decimal_to_Hex_Converter()
    elif choice == "4":
        print("\n")
        Binary_to_Hex_Converter()
    elif choice == "5":
        print("\n")
        Hex_to_Decimal_Converter()
    elif choice == "6":
        print("\n")
        Hex_to_Binary_Converter()
    else:
        print("\n")
        print("That was not an option, try again!")
        print("\n")
        main()
  

main()