Can you explain the filter(), map(), and reduce() functions?
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Python | filter(), map(), and reduce() Functions
- filter() function accepts two arguments, a function and an iterable, where each element of the iterable is filtered through the function to test if the item is accepted or not.
>>> set(filter(lambda x:x>4, range(7))) # {5, 6}
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map() function calls the specified function for each item of an iterable and returns a list of result
>>> set(map(lambda x:x**3, range(7))) # {0, 1, 64, 8, 216, 27, 125}
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reduce() function reduces a sequence pair-wise, repeatedly until we arrive at a single value..
>>> reduce(lambda x,y:y-x, [1,2,3,4,5]) # 3Let’s understand this:
2-1=1
3-1=2
4-2=2
5-2=3Hence, 3.
