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Python Python Collections (2016, retired 2019) Sets Set Math

fahad lashari
fahad lashari
7,693 Points
Posted by fahad lashari
fahad lashari
7,693 Points

In task two I just hacked together whatever solution I possibly could. Is there any better solution to this?

The loop works great. I just feel though that this could be improved even more. Any pointers?

kind regards,

Fahad

sets.py 
COURSES = {
    "Python Basics": {"Python", "functions", "variables",
                      "booleans", "integers", "floats",
                      "arrays", "strings", "exceptions",
                      "conditions", "input", "loops"},
    "Java Basics": {"Java", "strings", "variables",
                    "input", "exceptions", "integers",
                    "booleans", "loops"},
    "PHP Basics": {"PHP", "variables", "conditions",
                   "integers", "floats", "strings",
                   "booleans", "HTML"},
    "Ruby Basics": {"Ruby", "strings", "floats",
                    "integers", "conditions",
                    "functions", "input"}
}

def covers(topics):
    list1 = []
    for key, value in COURSES.items():
        if topics.intersection(value):
            list1.append(key)
    return list1     

def covers_all(topics):
    list1 = []
    for key, value in COURSES.items():
        if not topics.difference(value):
            list1.append(key)
    return list1

1 Answer

leonardbode
leonardbode
Courses Plus Student 4,011 Points

Fahad, you could use list comprehension.

def covers(topics):
    return [key for key, value in COURSES.items() if topics.intersection(value)]


def covers_all(topics):
    return [key for key, value in COURSES.items() if not topics.difference(value)]
fahad lashari
fahad lashari
7,693 Points
fahad lashari
fahad lashari
7,693 Points

Thanks! I never saw it from this angle. List comprehension still seems like a complete mystery to me. Any pointers for a good tutorial?

Kind regards,

Fahad

leonardbode
leonardbode
Courses Plus Student 4,011 Points

https://www.youtube.com/watch?v=3dt4OGnU5sM>

Remember, list comprehension should only be used if this does not make the code harder to read.

PEP20: Simple is better than complex. Complex is better than complicated.

Most importantly: Readability counts.

Leo

fahad lashari
fahad lashari
7,693 Points
fahad lashari
fahad lashari
7,693 Points

Leonard Bode

Cheers! I'll keep that in mind.

Have a great day =) !