Variables¶
Introduction¶
Let us see how to create variables in Python. In order to understand variables, I'd like you to meet Billy, he is a friendly dinosaur and is currently planning for his birthday party. Billy is very excited about the party and is busy thinking about packaging all the return gifts.
Billy has three type of return gifts -
- Balloons
- Party Hats
- Crackers
Declaring Variables¶
Let's start by creating a file called as 'variables.py' anywhere on your computer and open it in your code editor and type the following -
box = 'Baloons'
print(box)
In order to run the file, open the terminal and navigate to the directory which contains the file.
Suppose I have created that file on my desktop, then the path on my terminal will be -
$ cd /Users/{your username}/Desktop
In order to run the file, type the following in your terminal -
$ python3 variables.py
Output will be as follows -
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Congratulation! You just created a variable and printed its value.
Understanding Variables¶
Let us again have a look at the code we wrote above
box = 'Baloons'
print(box)
You are declaring a variable called box and assigning it a value of Baloons, note the single quote around it, you can also use double quotes as follows and it will give you the same output.
box = "Baloons"
print(box)
Single and double quotes can be used interchangeably, but be sure to use a consistent style all across your code.
Printing Values¶
box = 'Baloons'
print(box)
Line 2 prints the value of the variable 'box' to the terminal, which in our case is 'Baloons'.
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print() is a builtin python function which we can easily use to print values.
Re-assigning Values¶
Suppose, now Billy wants to pack 'Party Hats' instead of 'Baloons', then we can re-assign a new value to the same variable 'box'
box = 'Party Hats'
print(box)
You can again check the value by running the file
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Output
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Notice that our value has now changed from 'Baloons' to 'Party Hats'.
And now finally Billy wants to pack 'Crackers', so we can once again re-assign 'box' to a new value of 'Crackers'
box = 'Crackers'
print(box)
If you run the file again, this time output will be
1 |
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Full Code¶
# variables.py
box = 'Baloons'
print(box) # prints -> Baloons
box = 'Party Hats'
print(box) # prints -> Party Hats
box = 'Crackers'
print(box) # prints -> Crackers
Conclusion¶
As you must have noticed box is just a placeholder, we can assign different values to it from time to time, thus it is know as a variable, i.e values can change but the placeholder remains the same.