4. Python - Loops

For loop:


Loop through list

for element in listname:

        print(element, end=' ') // print element and a space


Loop through string:

for element in stringname:

        print(element, end=' ')


Normal I Loops:

for i in range(100):

        do something 100 times


While Loops:

while panda:

        print(1)


List comprehensions: (short way to write list loops)

squares = [n**2 for n in range(10)]

// puts each value after a loop into a list called squares.

// loop powers each n by 2

// LEFT = return value, MIDDLE = loop range, RIGHT = condition


short_planet = [planet for planet in planets if len(planet)<6]

// loop planet through planets list and see if its shorter than 6 characters and return if true


test = [True if n>givennumber else False for n in List]

// a if b else c

// takes in a list and a given number


ALT syntax:

[

    planet.upper() + '!' 

    for planet in planets 

    if len(planet) < 6

]

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