An algorithm for finding n interval ranges and Union sets by python

there are n ordered sets, and each element of the set is a range. Find the intersection of n sets, for example, the union of sets {[2jue 4], [9jue 13]} and {[6jue 12]} is {[2jue 4], [6jue 13]}. How to implement

with python?
Python
Feb.27,2021

python has an interval processing library interval 

from interval import Interval, IntervalSet

data = [(2, 4), (9, 13), (6, 12)]

intervals = IntervalSet([Interval.between(min, max) for min, max in data])
print [(_.lower_bound, _.upper_bound) for _ in intervals]

sort in the first step and traverse in the second step. 



: N 




-sharp -*- coding: utf-8 -*-
from functools import reduce


def intersection(range_a, range_b):
    """ None """
    if not (range_a and range_b):
        return None
    lower_a, upper_a = range_a
    lower_b, upper_b = range_b
    if lower_b < lower_a:
        if upper_b < lower_a:
            return None
        if upper_b < upper_a:
            return (lower_a, upper_b)
        return tuple(range_a)
    if lower_b < upper_a:
        if upper_b < upper_a:
            return tuple(range_b)
        return (lower_b, upper_a)
    return None


def intersectionN(ranges):
    """  N None """
    return reduce(intersection, ranges)


def _test_intersection_algorithm(f):
    """
     f

    -sharp 
      * i:  
      * i+1: 

    -sharp 
       (3,6)  (x,y) :
      1. x < 3,     y < 3
      2. x < 3, 3 < y < 6
      3. x < 3, 6 < y

      4. 3 < x < 6,     y < 6
      5. 3 < x < 6, 6 < y

      6. 6 < x, 6 < y
    """
    test_records = [
        [(3, 6), (1, 2)],   None,
        [(3, 6), (1, 4)],   (3, 4),
        [(3, 6), (1, 7)],   (3, 6),

        [(3, 6), (4, 5)],   (4, 5),
        [(3, 6), (4, 7)],   (4, 6),

        [(3, 6), (7, 9)],   None,
    ]

    for i in range(len(test_records)/2):
        input_set = test_records[2*i]
        expected = test_records[2*i+1]
        assert f(input_set) == expected, (
            'input: %s, expected: %s' % (input_set, expected))


def test_intersection():
    -sharp  pytest 
    _test_intersection_algorithm(intersectionN)


 and so on, you can implement the union algorithm.

Previous: The background image that is dynamically added to the div after the resource is requested in vue, why can't it be displayed?

Next: Hbuilder cannot call emmet

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
© 2021 CodesHelper
Advertising Contact us About us
Menu