Python Beginner: I need a basic explanation on returns

I’m simply at the starting point of my coding journey. I’m trying to understand returns as a function but I simply cannot grasp the explanations I’ve seen.

Is there anyone here who would be able to give me a layman’s explanation or even guide to some resource for people in my position?

Thanks!

Sure, welcome to the forums!

I think of functions as magic boxes that do things and sometimes return outputs.
In math you might see something like y=2x be expressed as f(x)=2x.

In this case, f(x) is a function and it takes an input of x. So if I put one book into this magic box, the box will give me 2 of that book. If i put 10 dollars, it’ll give me 20 dollars (love this box).

In code that might look like:

``````def double_your_thing(x):
return 2*x

print(double_your_thing("fun"))
#output 'funfun'
``````

Sometimes there are functions that don’t return things, but when you use them they perform an action (which you might see or not see). For example, if I put money in the bank, I don’t see the physical money anymore. The bank performs the action of storing the money.

``````savings =0
def deposit_money(cash):
savings += cash

deposit_money(10)
print("\$" + savings)
#output: \$10
``````

Finally, sometimes you have functions that don’t output anything and also don’t take input, they just perform an automatic action.

``````def greeting():
print("Hello there!")

greeting()
#output "Hello there!"
#note since greeting() already prints, if you write
#print(greeting()) you won't get your desired output``````
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A function that takes in a one inch thick chuck steak and returns a tray of 1" X 1" cubes of meat.

``````def cube_steak (steak):
# trim excess fat
# remove any bone
# cut into 1" strips
# cut strips into 1" cubes
``````

A function to grind trimmed and cubed meat to make ground chuck

``````def meat_grinder(meat):
# place cube in grinder receiver
# press down with wooden press tool
# turn handle slowly
# let ground meat fall onto a tray
# repeat above steps until all cubes are ground
# return tray of ground meat to the prep table
``````

Both of these functions return the outcome of the steps carried out in each one.

2 Likes

Now I’m just hungry…

3 Likes

Y’all are amazing, thank you!!! I was able to get myself unstuck. I would like to share the exercise I was working on and what I was able to do in order to finish the project. I was struggling to get my_age to hold it’s value.

Instructions:

1. The function `calculate_age` in script.py creates a variable called `age` that is the difference between the current year, and a birth year, both of which are inputs of the function. Add a line to return `age` .
2. Outside of the function, call `calculate_age` with values `2049` ( `current_year` ) and `1993` ( `birth_year` ) and save the value to a variable called `my_age` .
3. Call `calculate_age` with values `2049` ( `current_year` ) and `1953` ( `birth_year` ) and save the value to a variable called `dads_age` .

Print the string `"I am X years old and my dad is Y years old"` to the console, with `my_age` where the `X` is and `dads_age` where the `Y` is.`
-------------------------------------code-------------------------------------
I am adding below the code I did:

def calculate_age(current_year, birth_year):
age = current_year - birth_year
return (age)
current_year = 2049

#originally put as ‘birth_year: 1993’ to calculate my own birth year, then I couldn’t figure out how to get it to hold the value as my_age so I changed the birth year to 1953 in order to calculate dads_age
birth_year = 1953

#my age - uses birth year 1993 ( later changed to 1953 to get dads_age so I added a result to hold the value
my_age = (current_year - birth_year)
my_age_result = 56
print(str(my_age_result))

#printing statement
print ("I am ", my_age_result, "years old and my dad is ", dads_age_result, “years old!”)

What I got:
56
96
I am 56 years old and my dad is 96 years old!

Did I format the code in the correct way? Especially when changing my_age to dads_age and having to use both in the final statement…I was struggling pretty hard with understanding why I couldn’t just get the code to remember my_age

Thank you for your contributions!! Without you all, I would’ve still been stuck!

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Hi, great!

When you past your code, you have to press the button and paste it between the tick marks to preserve formatting (otherwise it’s hard to tell what’s happening, specially in python).

In python it’s always a consideration to consider how indentation affects the scope of your code.

For example:

``````def something():
number = 1000

print(number)
#this will throw an error because number doesn't exist outside the scope of something()
``````
1 Like