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Boolean type in Python

Boolean values in Python are represented as two constants True and False.

True and False constants are simply set to integer values of 1 and 0, i.e True is represented as 1 and False is represented as 0. In simple way, True and False are alternative ways to spell integer values 1 and 0.

Note: True should have uppercase ‘T’ and False should have uppercase ‘F’. Using a lowercase t and f throws error.

The type object for this new type is named bool.

x = True
print(type(x))

Output

<class 'bool'>

Arithmetic operation using a Boolean in Python

The Boolean type is a subclass of int class, so we can perform arithmetic using a Boolean.

t = True
f = False
print('t + 1 = ',t + 1)
print('10 - t = ',10 - t)
print('10 - f = ',10 - f)
print('10 * f = ',10 * f)
print('5/t = ', 5/t)
print('f/t = ', f/t)

Output

t + 1 =  2
10 - t =  9
10 - f =  10
10 * f =  0
5/t =  5.0
f/t =  0.0

Integers, Floats and String as Boolean

Numbers can be converted to boolean type using Python’s bool() function.

Pretty much everything which has a content evaluates to True.

An integer, float or complex number having value 0 returns False. An integer, float or complex number set to any other number, positive or negative, returns True.

print("bool(0): ", bool(0))
print("bool(1.5): ", bool(1.5))
print("bool(-5): ", bool(-5))
print("bool('hello'): ", bool("hello"))
print("bool(['Sunday','Monday']): ", bool(['Sunday','Monday']))

Output

bool(1.5):  True
bool(-5):  True
bool('hello'):  True
bool(['Sunday','Monday']):  True

Empty value evaluates False

print('bool(False): ', bool(False))
print('bool(None): ', bool(None))
print('bool(0): ', bool(0))
print('bool(""): ', bool(""))
print('bool(()): ', bool(()))
print('bool([]): ', bool([]))
print('bool({}): ', bool({})) 

Output

bool(False):  False
bool(None):  False
bool(0):  False
bool(""):  False
bool(()):  False
bool([]):  False
bool({}):  False