DEV Community

Cover image for Learn Python: Booleans & Comparisons
Rishi
Rishi

Posted on • Edited on

1 2

Learn Python: Booleans & Comparisons

Simply Booleans

Checking for truthy or falsy.

Description Operator
Truthy True
Falsy False
Greater than >
Less than <
Greater or equal to >=
Less or equal to <=
Equals to ==
Assignment =
truthy = True
falsy = False
print(truthy);
print(falsy);

LEGAL_AGE = 18
age = int(input("Enter your age:"));
is_over_legal_age = age >= LEGAL_AGE;
print(f"User is OVER legal age: {is_over_legal_age}")

is_under_legal_age = age < LEGAL_AGE;
print(f"User is UNDER legal age: {is_under_legal_age}")

is_twenty = age == 20;
print(f"User is 20 years old: {is_twenty}")

is_eighteen = age == 18;
print(f"User is 18 years old: {is_eighteen}")
Enter fullscreen mode Exit fullscreen mode

bool()

bool() is a function which takes in a parameter and evaluates it to either True or False.

print(f"Integer 0 is evaluated to: {bool(0)}")
print(f"An empty character '' is evaluated to: {bool('')}")
print(f"Positve number 1 is evaluated to : {bool(1)}")
print(f"Negative -1 is evaluated to: {bool(-1)}")
print(f"A string 'abc' is evaluated to : {bool('abc')}")
Enter fullscreen mode Exit fullscreen mode

and

and gives you the first value if it is False, otherwise, it gives you the second value.

print(f"True and True: { True and True}");
print(f"False and False: { False and False}");
print(f"True and False: { True and False}");
print(f"False and True: { False and True}");
Enter fullscreen mode Exit fullscreen mode

Let's compare some numbers and some strings.

print(f"True and True: { bool(10) and bool(10)}");
print(f"False and False: { bool(0) and bool(10)}");
print(f"True and False: { bool(10) and bool(0)}");
print(f"False and True: { bool(0) and bool(10)}");
print()
print(f"10  and  10: { 10 and 10}");
print(f"0  and   0:  { 0 and 0}");
print(f"10  and   0:  { 10 and 0}");
print(f"0  and  10:  { 0 and 10}");
print()
print(f"'abc'  and  'xyz': { 'abc' and 'xyz'}");
print(f"''  and  '': { '' and 'xyz'}");
print(f"'abc'  and  '': { 'abc' and ''}");
print(f"''  and  'xyz': { '' and 'xyz'}");
Enter fullscreen mode Exit fullscreen mode

or

or gives you the first value if it is True, otherwise it gives you the second value.

print(f"True or True: { True or True}");
print(f"False or False: { False or False}");
print(f"True or False: { True or False}");
print(f"False or True: { False or True}");

Enter fullscreen mode Exit fullscreen mode

Let's compare some numbers and some strings.

print(f"True or True: { bool(10) or bool(10)}");
print(f"False or False: { bool(0) or bool(10)}");
print(f"True or False: { bool(10) or bool(0)}");
print(f"False or True: { bool(0) or bool(10)}");
print()
print(f"10  or  10: { 10 or 10}");
print(f"0  or   0:  { 0 or 0}");
print(f"10  or   0:  { 10 or 0}");
print(f"0  or  10:  { 0 or 10}");
print()
print(f"'abc'  or  'xyz': { 'abc' or 'xyz'}");
print(f"''  or  '': { '' or 'xyz'}");
print(f"'abc'  or  '': { 'abc' or ''}");
print(f"''  or  'xyz': { '' or 'xyz'}");
Enter fullscreen mode Exit fullscreen mode

not

not negates any boolean value.
not True is evaluated to False.
not False is evaluated to True.

print(f"True: { True}" );
print(f"not True: {not True}" );
print()
print(f"False: { False}" );
print(f"not False: {not False}" );
print()
print(f"35: { 35}" );
print(f"not 35: {not 35}" );
print()
print(f"'': { ''}" );
print(f"not '': {not ''}" );
print()
print(f"'abc': { 'abc'}" );
print(f"not 'abc': {not 'abc'}" );
Enter fullscreen mode Exit fullscreen mode



AWS Security LIVE!

Join us for AWS Security LIVE!

Discover the future of cloud security. Tune in live for trends, tips, and solutions from AWS and AWS Partners.

Learn More

Top comments (0)

AWS Security LIVE!

Tune in for AWS Security LIVE!

Join AWS Security LIVE! for expert insights and actionable tips to protect your organization and keep security teams prepared.

Learn More

👋 Kindness is contagious

Dive into an ocean of knowledge with this thought-provoking post, revered deeply within the supportive DEV Community. Developers of all levels are welcome to join and enhance our collective intelligence.

Saying a simple "thank you" can brighten someone's day. Share your gratitude in the comments below!

On DEV, sharing ideas eases our path and fortifies our community connections. Found this helpful? Sending a quick thanks to the author can be profoundly valued.

Okay