in python, does `is not int` ever return false?

When I do this:

>>> 1 is int
False

It returns False, even when I would expect it to return True. The same behavior occurs when attempting to type-check a variable.

>>> a = 1 >>>
   a is int
False

I understand that this has something to do with using is instead of isinstance or type.

>>> type(1)
<class 'int'>
   >>> isinstance(1, int)
   True
   >>> type(1) is int
   True

Suggestion : 2

Operations and built-in functions that have a Boolean result always return 0 or False for false and 1 or True for true, unless otherwise stated. (Important exception: the Boolean operations or and and always return one of their operands.),The only operation that immutable sequence types generally implement that is not also implemented by mutable sequence types is support for the hash() built-in.,Any object can be tested for truth value, for use in an if or while condition or as operand of the Boolean operations below.,The implementation adds a few special read-only attributes to several object types, where they are relevant. Some of these are not reported by the dir() built-in function.

>>> n = -37 >>>
   bin(n)
'-0b100101' >>>
n.bit_length()
6

def bit_length(self):
   s = bin(self) # binary representation: bin(-37) -- > '-0b100101'
s = s.lstrip('-0b') # remove leading zeros and minus sign
return len(s) # len('100101') -- > 6

>>> n = 19 >>>
   bin(n)
'0b10011' >>>
n.bit_count()
3
   >>>
   (-n).bit_count()
3

def bit_count(self):
   return bin(self).count("1")

>>> (1024).to_bytes(2, byteorder = 'big')
b '\x04\x00' >>>
   (1024).to_bytes(10, byteorder = 'big')
b '\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00' >>>
   (-1024).to_bytes(10, byteorder = 'big', signed = True)
b '\xff\xff\xff\xff\xff\xff\xff\xff\xfc\x00' >>>
   x = 1000 >>>
   x.to_bytes((x.bit_length() + 7) // 8, byteorder='little')
      b '\xe8\x03'

>>> int.from_bytes(b '\x00\x10', byteorder = 'big')
16
   >>>
   int.from_bytes(b '\x00\x10', byteorder = 'little')
4096
   >>>
   int.from_bytes(b '\xfc\x00', byteorder = 'big', signed = True) -
   1024 >>>
   int.from_bytes(b '\xfc\x00', byteorder = 'big', signed = False)
64512
   >>>
   int.from_bytes([255, 0, 0], byteorder = 'big')
16711680

Suggestion : 3

But, if they enter something that isn’t a number they get an error. The reason is that this if statement will always be True. This is because of a concept called TRUTHVALUES. When Python has an if statement it checks the TRUTHVALUES of the statements. Now almost all values in Python are True. The only values that are False are False, None, 0 or any equivalent number-type, and any empty container like [] () {} set() "" ''. Everything else is True. ,To clarify more, the statement: [if float] is always True because you don’t compare it with something, float by it’s own is float and logically just a True value by it’s own.Only if it was [If type(a) == float] could sometimes be False,This works IRL but in the editor it doesn’t. It’s a built in function that allows returns of correct true or false values based on the type validation.,Yes!!! I saw first this tip but I ignored it when I was with this problem (the TRUTHVALUE problem) in the Review.01. I skipped it and only then solving the same problem in the Review.03 I realised that both were the same problem. So, a big Thank you!!! :)

Many people have been writing the following code to check if the number entered is an integer or a float

def distance_from_zero(a):
   if type(a) == int or float:
   ....

Thus, when someone writes or float they are really writing or True. To get around this we would need to check each one individually like so -

if type(a) == int or type(a) == float:

This code works fine despite what Code Academy says:

def distance_from_zero(a):
   if type(a) == int or type(a) == float:
   print abs(a)
else:
   print 'Not an integer or a floating point decimal!'

distance_from_zero(-5)

def distance_from_zero(a):
   if type(a) == int or type(a) == float:
   return abs(a)
else:
   return "Nope"

def distance_from_zero(n):
   if type(n) == int:
   return abs(n)
elif type(n) == float:
   return abs(n)
else:
   return "Not an integer or float!"
distance_from_zero(10)

it seems to be right:

def distance_from_zero(s):
   if type(s) == int or type(s) == float:
   return abs(s)
else:
   return 'Not an integer or float!'
distance_from_zero(-10)

def distance_from_zero(m):
   if type(m) == int or type(m) == float:
   return abs(m)
else:
   return "Not an integer or float!"

print distance_from_zero(-- - 3.34-- -- -- -- - 45)

Suggestion : 4

Any list, tuple, set, and dictionary are True, except empty ones.,The following will return True:,The bool() function allows you to evaluate any value, and give you True or False in return,,The following will return False:

print(10 > 9)

Suggestion : 5

Last Updated : 20 Aug, 2022,Technical Scripter 2020

Output:

<class 'bool'>
   <class 'bool'>

Syntax:

bool([x])

False
False
False
False
False
True

False
False
False
False
False
True

True
Atleast one number has boolean value as True

False
Atleast one number has boolean value as False

Boolean value of a is False