Python code to convert Integer into Binary

Question

I need a code in Python 3.3 to convert an integer into binary. This is my first try:

a = input(str("Please Enter a Number")
if a == float:
 print (1)
else print(0)
b = a/2
while True:
 if b == float:
 print(1)
 else print(0)

I don't know why I keep getting errors with the if a == float:. And I know that the rest of the code is wrong too, but this : makes me crazy.

• Chris: What are you trying to accomplish with "if a == float:"?
• hankd: What is float in this case?
• Chris: Also, what are you trying to accomplish with your while loop?
• Robᵩ: John, welcome to Stack Overflow. I notice that your post does not include a question. Maybe you are asking "How do I convert integer to binary?" Or maybe you are asking "why doesn't a == float do what I want?" Since you didn't ask a question, it is hard to know which question to answer. Please edit your post to include a specific question.
• Robᵩ: Nah, I try to complain about only one thing at a time, particularly with new members. I haven't figured out how to say "ENOQUESTION" and "SSCCE.ORG" in one breath.

Answer 1

Your code has a lot of issues:

1. Your indentation is off. Indentation is very important in Python since that is how it knows what goes with what.
2. You need to use isinstance to see if an object is a float. I assume this is what you are trying to do with a == float. But, that doesn't make sense because, in Python 3.x., input always returns a string object. So, a is a string. However, if float is actually a variable, then you should change its name. Naming a variable float is a bad practice since it overrides the built-in.
3. You are missing a colon at the end of each else.
4. You are missing a closing parenthesis on the first line.
5. The str in the first line is unnecessary (not an error, but I just thought I'd mention it).

However, instead of fixing all this, I'm going to introduce you to the bin built-in:

>>> n = 127
>>> bin(n)
>>> # The "0b" at the start means "binary".
'0b1111111'
>>> # This gets rid of the "0b"
>>> bin(n)[2:]
'1111111'
>>>

It was built explicitly to do what you are trying to do.

Also, here are some references on Python you might enjoy:

http://www.tutorialspoint.com/python/python_overview.htm

http://wiki.python.org/moin/BeginnersGuide/Programmers

• SethMMorton: Not to mention there's a missing closing parenthesis on the first line.
• Robφ: I'm not convinced that a == float is a type test. He might actually have a variable named float.
• user2555451: Yea, I don't know precisely either. Let me amend my post.

Answer 2

You can just use the bin function:

>>> bin(100)
'0b1100100'

Ignore the 0b infront of the string. You can always get the raw binary numbers using using bin(your_numer)[2:].

Also, you can get this using the format function:

>>> format(100, 'b')
'1100100'

Answer 3

If you need to print it in binary you can just do: print(bin(a))

Answer 4

This is what i made

while True:
 print("FIND OUT WHAT BINARY THIS IS")
 space = " "
 num1 = int(input())
 while num1 > 0:
 if num1 % 2 == 0:
 space = space + "0"
 else:
 space = space + "1"
 num1 = int(num1 / 2)
 else:
 space = space[::-1]
 print(space)