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Is there a way in python to call filter on a list where the filtering function has a number of arguments bound during the call. For example is there a way to do something like this:
>> def foo(a,b,c): return a < b and b < c >> myList = (1,2,3,4,5,6) >> filter(foo(a=1,c=4),myList) >> (2,3) This is to say is there a way to call foo such that a=1, c=4, and b gets bound to the values in myList?
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Python Filter List with Condition. You can define any complicated condition on a list element to decide whether to filter it out or not. Just create your own function (e.g., condition(x) ) that takes one list element as input and returns the Boolean value True if the condition is met or False otherwise.
filter() method is a very useful method of Python. One or more data values can be filtered from any string or list or dictionary in Python by using filter() method. It filters data based on any particular condition. It stores data when the condition returns true and discard data when returns false.
The filter function takes two parameters: Function: Function that tests if elements of an iterable are True or false. If none, the function defaults to identity function returning false if any elements are false. Iterable: Iterable which is to be filtered could be sets, tuples, lists or containers of any iterators.
You can send any data types of argument to a function (string, number, list, dictionary etc.), and it will be treated as the same data type inside the function.
Python Filter() Function. The filter() function accepts only two parameters. The first argument is the name of a user-defined function, and second is iterable like a list, string, set, tuple, etc. It calls the given function for every element of iterable, just like in a loop.
The filter () function iterates over the elements of the list and applies the fn () function to each element. It returns an iterator for the elements where the fn () returns True. In fact, you can pass any iterable to the second argument of the filter () function, not just a list.
Passing a List as an Argument. You can send any data types of argument to a function (string, number, list, dictionary etc.), and it will be treated as the same data type inside the function. E.g. if you send a List as an argument, it will still be a List when it reaches the function:
Yes, you can call filter () without passing an actual function as the first argument. Instead, you can specify it as None. When None is specified in the filter (), then it pops out all elements that evaluate to False. Let’s consider the following list for illustration:
One approach is to use lambda:
>>> def foo(a, b, c): ... return a < b and b < c ... >>> myTuple = (1, 2, 3, 4, 5, 6) >>> filter(lambda x: foo(1, x, 4), myTuple) (2, 3) Another is to use partial:
>>> from functools import partial >>> filter(partial(foo, 1, c=4), myTuple) (2, 3) If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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