all numbers are stored in binary. if you want a textual representation of a given number in binary, use bin(i)
>>> bin(10)
'0b1010'
>>> 0b1010
10
Answer from aaronasterling on Stack Overflow Top answer 1 of 8
293
all numbers are stored in binary. if you want a textual representation of a given number in binary, use bin(i)
>>> bin(10)
'0b1010'
>>> 0b1010
10
2 of 8
92
Without the 0b in front:
"{0:b}".format(int_value)
Starting with Python 3.6 you can also use formatted string literal or f-string, --- PEP:
f"{int_value:b}"
Top answer 1 of 9
105
You can use int and set the base to 2 (for binary):
>>> binary = raw_input('enter a number: ')
enter a number: 11001
>>> int(binary, 2)
25
>>>
However, if you cannot use int like that, then you could always do this:
binary = raw_input('enter a number: ')
decimal = 0
for digit in binary:
decimal = decimal*2 + int(digit)
print decimal
Below is a demonstration:
>>> binary = raw_input('enter a number: ')
enter a number: 11001
>>> decimal = 0
>>> for digit in binary:
... decimal = decimal*2 + int(digit)
...
>>> print decimal
25
>>>
2 of 9
36
Binary to Decimal
int(binaryString, 2)
Decimal to Binary
format(decimal ,"b")
ps: I understand that the author doesn't want a built-in function. But this question comes up on the google feed even for those who are okay with in-built function.
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Using a function keeps code organized and reusable. It allows multiple binary inputs to be converted easily and avoids repeating conversion logic throughout the program.
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Python can handle very large binary numbers as strings. Conversion using loops or int(binary_str, 2) works efficiently without integer overflow.
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We can use the built-in int() function to convert binary numbers into decimals. The int() function converts the binary string in base 2 number. binary_string = input("Enter a binary number :") try: decimal = int(binary_string,2) print("The decimal value is :", decimal) except ValueError: ...
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