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Python - Filter
Python's filter() function is a built-in higher-order function that allows you to filter elements of an iterable (like a list, tuple, or set) based on a specific condition. The function takes two arguments: a function that tests the condition, and an iterable with elements to be filtered. The filtering function should take one input and return a boolean value (True or False), indicating whether the input meets the condition or not.
When you apply the filter() function, it iterates over the input iterable and calls the filtering function for each element. If the filtering function returns True for an element, that element is included in the result. If it returns False, the element is excluded from the result. The filter() function returns an iterator containing the filtered elements, which can be converted into a list, tuple, or another iterable type as needed.
In Python, you can pass any function, including lambda functions, as the filtering function. Lambda functions are anonymous functions defined with the lambda keyword, and they can be used to create small, one-time-use functions directly within the filter() call.
The filter() function is especially useful when working with large datasets or when you need to apply complex filtering logic. By using filter() along with lambda functions or other custom functions, you can create more readable and concise code for filtering operations.
Examples :
Followings are the list of examples showing various usage and operation of the filter()
NOTE 1 : All the examples in this page are written in Python 3.x. It may not work if you use Pyton 2.x NOTE 2 : All the examples in this page are assumed to be written/run on Windows 7 unless specifically mentioned. You MAY (or may not) need to modify the syntax a little bit if you are running on other operating system.
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