Python Bin() Function

Function Name:


Function Overview:

The bin() function returns the binary representation of an int object as a string.

It takes an integer in decimal format and converts it to binary format.

The returned value is of type string containing the binary value of the integer.

The binary string will have a prefix '0b' denoting binary value.


Remember that the returned binary string is a valid python expression which can be passed inside the function eval() to get the integer value back.


For the bin() function to work on any other object representing an integer value

the class corresponding that object has to defined with a __index__() method.




# Define an integer value

x = 10


# convert the integer to a binary string

binaryString = bin(x)


print("Binary string of {} is {}".format(x, binaryString))


#convert the binary back to decimal

y = eval(binaryString)


print("Binary converted back to decimal:{}".format(y))



Binary string of 10 is 0b1010

Binary converted back to decimal:10



# class representing a numeric val

class IntClass:

    myVal = 0


    def __init__(self, aVal_in):

        self.myVal = aVal_in


    #Has to define the __index__() method

    def __index__(self):

        return self.myVal


#Use bin() to convert an IntClass instance

CustomInt       =  IntClass(2)

CustomIntBinary = bin(CustomInt)


print("Custom integer object as binary string:{}".format(CustomIntBinary))




Custom integer object as binary string:0b10



The bin() function will raise a TypeError if an invalid type like a floating point value is passed as a parameter.



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