I am trying to find an efficient solution for finding overlapping of n rectangles where rectangles are stored in two separate lists. We are looking for all rectangles in listA
that overlap with rectangles in listB
(and vice versa). Comparing one element from the first list to second list could take immensely large amount of time. I am looking for an efficient solution.
I have two lists of axis-aligned rectangles:
rect = Rectangle(10, 112, 56, 15)
rect2 = Rectangle(0, 0, 1, 15)
rect3 = Rectangle (10, 12, 56, 15)
listA = [rect, rect2]
listB= [rect3]
which is created from the class:
import numpy as np
import itertools as it
class Rectangle(object):
def __init__(self, left, right, bottom, top):
self. left = left
self.bottom = bottom
self.right = right
self.top = top
def overlap(r1, r2):
hoverlaps = True
voverlaps = True
if r1.left > r2.right or r1.right < r2.left:
hoverlaps = False
if r1.top < r2.bottom or r1.bottom > r2.top:
voverlaps = False
return hoverlaps and voverlaps
I need to compare rectangle in listA
to listB
the code goes like this which is highly inefficient - comparing one by one
for a in it.combinations(listB) :
for b in it.combinations(listA):
if a.overlap(b):
Any better efficient method to deal with the problem?
listA = [...]; listB = [...];
, and we are looking for all rectangles in listA that overlap with rectangles in listB (and vice versa)? Or that we are looking for the region that is the overlap of all rectangles? Or something else? \$\endgroup\$for a,b in it.combinations(listA,2):
: I see only one list used here, what islistB
good for? Also can you provide a bit more context around thisfor
loop (what do you do when they overlap, how do you initialize stuff if any)? \$\endgroup\$Rectangle
:radious
, in particular.) \$\endgroup\$