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Well done!
You have completed Python Comprehensions!
You have completed Python Comprehensions!
Preview
A set is another iterable that can be created using comprehension. Let’s dive into its syntax!
The Syntax
# basic
{expression for temp_var in iterable}
# with a conditional
{expression for temp_var in iterable if condition}
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Another Python datatype
that can be created using
0:00
comprehension syntax is a set.
0:04
Since a set is so similar to a list,
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the comprehension syntax
is almost identical.
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Here's the syntax for
a list comprehension.
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And here's the syntax for
a set comprehension.
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It's easy to miss, but our square
brackets are now curly brackets.
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Python set syntax uses curly brackets.
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So naturally set comprehension
syntax will also use curly brackets.
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Let's explore set comprehension.
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Open up set comprehension.pi.
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As always, you'll see two loops,
two syntax templates, and
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two print statements.
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We have a pretty common use of
sets here in the first loop,
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removing duplicate values.
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We have a list of test scores, and
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we're looping through each one
to add to the unique scores set.
1:00
Any duplicates will be removed
due to the nature of sets.
1:05
The second loop adds a condition and
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will only add scores that
are greater than 70 to the new set.
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Let's see them both in
action by running the file.
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Python3 6, tab, enter.
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Our first set has removed
the duplicate 74, and
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our second set only contains
scores higher than 70.
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Let's jump into refactoring.
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We'll first uncomment the template syntax,
and off we go.
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Original iterable is our
list of test scores.
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Temporary variable is our score.
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And our expression is simply score yet
again.
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Super easy,
just like our first list comprehension.
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Let's refactor the other
one before we run the file.
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Now, instead of plugging
in variables again,
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we can just grab the set comprehension
from the first example and add to it.
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So let's do that.
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Grab the set, uncomment this,
and just replace it.
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Now we know there's a conditional here,
but which type is it?
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And where would it go
in the comprehension?
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Pause the video and
take some time to give this a go yourself.
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I'll be here.
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How did it go?
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Here's what I did.
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We want to filter out
everything less than 70.
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So the conditional affects the list.
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The condition will therefore be
at the end of the comprehension.
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Let's add it, if score is over 70.
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Now, let's save the file and run it.
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And we've got an identical output.
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Good refactoring.
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You can now add set
comprehensions to your tool belt.
3:04
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