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Mohamed M El-Kalioby
Mohamed M El-Kalioby Subscriber

Posted on • Updated on

Filter🐍 Python Iterables by Complex Queries

Python filter built-in function allows filtering Python iterables by function that shall return True/False. The problem with it ,that you can easily pass a query to that function to filter the iterable.

Example of Python filter

def filter_age(item):
    return item["age"] > 19
l = [{"name":"John","age":16}, {"name":"Mike","age":19},{"name":"Sarah","age":21}]
print(list(filter(filter_age,l)))
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output

[{'name': 'Sarah', 'age': 21}]
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What if you want to pass the age as parameter to filter_age function. This will need a partial which isn't complex but isn't comprehensive enough.

Leopards

Leopards is a Python library that provides an easy and fast way to filter members of a list or a tuple. The member can be a dict or object. The library supports AND, OR and NOT implementations.

Example

from leopards import Q
l = [{"name":"Karen","age":"16"}, {"name":"Mike","age":"19"},{"name":"Sarah","age":"21"}]
filtered= Q(l,{'name__icontains':"k", "age__gt":16})
print(list(filtered))
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output

[{'name': 'Mike', 'age': '19'}]
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For more examples and how to install/ use the library. Please check the github repo.

GitHub logo mkalioby / leopards

Query your python lists

Leopards

PyPI version Python Versions Coverage build status

Leopards is a way to query list of dictionaries or objects as if you are filtering in DBMS You can get dicts/objects that are matched by OR, AND or NOT or all of them As you can see in the comparison they are much faster than Pandas.

Installation

pip install leopards
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Usage

from leopards import Q
l = [{"name":"John","age":"16"}, {"name":"Mike","age":"19"},{"name":"Sarah","age":"21"}]
filtered= Q(l,{'name__contains':"k", "age__lt":20})
print(list(filtered))
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output

[{'name': 'Mike', 'age': '19'}]
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The above filtration can be written as

from leopards import Q
l = [{"name": "John", "age": "16"}, {"name": "Mike", "age": "19"}, {"name": "Sarah"
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Happy Coding.

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