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Vicki Langer
Vicki Langer

Posted on • Updated on

Charming the Python: Boolean & Operators

If coding tutorials with math examples are the bane of your existence, keep reading. This series uses relatable examples like dogs and cats.


Boolean & Operators

  • Boolean
  • Operators
    • Arithmetic
    • Comparison
    • Logical

Boolean

True or False are the only possibilities with a boolean. However, you can use them for yes/no questions and many other things too.

is_dog = False
is_coding = True
is_programmer = True
is_cat = False
is_human = true  # this is true, but will error because it isn't capitalized
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True and False are constants with the values 1 & 0

True == 1
False == 0
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Operators

Operators are the constructs which can manipulate the value of operands. -reference

+ - * / % // **  # math or arithmetic operators
== != < > <> >= <=  # comparison operators
and or not  # logical operators
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Arithmetic Operators

I gave a bunch of examples in the post below.

Comparison Operators

you can compare numbers, words, lists, and more

Operator What it is Example
== equals 2 == 2
!= does not equal 2 != 7
> greater than 9 > 2
>= greater than or equal to 9 >= 9 or 9 >= 7
< less than 4 < 6
<= less than or equal to 4 <= 7

Logical Operators

and or not are useful for making decisions

dog_needs_exercise = True
is_awake = True

if dog_needs_exercise and is_awake:
    print("Take dog for a walk")
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dog_hungry = False
is_dinner_time = True

if dog_hungry or is_dinner_time:
    print("Feed dog")
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# getting paid this week?

a = "go to work"
b = "get work done"

if a and b:
    print("You get paid")  # because you did both

if a or b:
    print("You won't get paid")  # because you didn't do both
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Series based on

Top comments (9)

 
vickilanger profile image
Vicki Langer

As mentioned before, True/False is actually 1/0. So, are you saying we should be using and & or to evaluate to 1/0?

I’ve tried to find examples that don’t lead to a Boolean outcome and I’m at a loss.

I read the python docs this morning and it refers to these as Boolean operators.

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vickilanger profile image
Vicki Langer

Thanks for letting me know.

I've added a note about the values.

I know and & or don't directly evaluate to True & False. I was trying to simplify the example, but I think I oversimplified it. I'll come up with something that doesn't come across that way. I wanted to make sure if a beginner comes across the post that it's not using anything too advanced.

 
vickilanger profile image
Vicki Langer • Edited

So, part of my problem understanding your original post was that I had never seen assert before. I've read up on it and now I think I can make sense of this.

If I'm now understanding correctly, and & or statements seem similar to if, else, and elif statements.

I'm thinking something like this is a simple enough example.

dog_hungry = False
is_dinner_time = True

if dog_hungry or is_dinner_time:
    print("Feed dog")
 
vickilanger profile image
Vicki Langer

I definitely don’t want it to be incorrect. The only example I keep thinking of is a while loop, but that’s a bit more advanced than the current notes.