intersection

问题 I have a square in 2d space (width = height). The square is currently defined by two points: BottomLeft(X1,Y1) and TopRight(X2,Y2). The square is axis-aligned, so finding the other two corners is as easy as (X1, Y2) and (X2, Y1). I also have two points - one is always inside the square, and the other is definitely outside. They aren't necessarily at the centre of the square - they can be wherever. I know their coordinates too. What I need is to find the intersection point between the line

问题 Question is a follow up to Powershell find common string in multiple files Following PowerShell code goes through a directory for each file, extract IP addresses and store in multi-dimensional array $match after iteration, go through each element in the multi-dimensional array and split by space, and store into another multi-dimensional array $j I am able to find the intersection between $j[0] and $j[1] , but I'm not sure how to do this iteratively, over all the elements of $j , the array of

问题 My question is, how can we apply intersection for 5~7 sets. Suppose each set having set of elements. please help me in creating an algorithm for this and what will be the complexity of this process. 回答1: A straight forward method: I = S_1; For each set s in S_2 ... S_N: For each element ei in I: if ei not in s remove ei from I endif endfor endfor With this the complexity is m^2xN if each set has m elements and there are N sets. If sets are sorted then you can have mlog(m)N with binary search

问题 My question is, how can we apply intersection for 5~7 sets. Suppose each set having set of elements. please help me in creating an algorithm for this and what will be the complexity of this process. 回答1: A straight forward method: I = S_1; For each set s in S_2 ... S_N: For each element ei in I: if ei not in s remove ei from I endif endfor endfor With this the complexity is m^2xN if each set has m elements and there are N sets. If sets are sorted then you can have mlog(m)N with binary search

问题 My question is, how can we apply intersection for 5~7 sets. Suppose each set having set of elements. please help me in creating an algorithm for this and what will be the complexity of this process. 回答1: A straight forward method: I = S_1; For each set s in S_2 ... S_N: For each element ei in I: if ei not in s remove ei from I endif endfor endfor With this the complexity is m^2xN if each set has m elements and there are N sets. If sets are sorted then you can have mlog(m)N with binary search

问题 I'm trying to find the shared elements (and the shared number of occurrences) between two lists. For example, the intersection of these two lists: a = [1, 1, 2, 3, 4, 5, 6, 7, 8, 1] b = [1, 1, 3, 5, 7, 9] should return Counter({1: 2, 3: 1, 5: 1, 7: 1}) or something similar, e.g. {1: 2, 3: 1, 5: 1, 7: 1} or [1, 1, 3, 5, 7] (order of the list doesn't matter). I already have an approach that works: cnts_a = Counter(a) cnts_b = Counter(b) cnts_a_b = Counter() # counter for the shared values for

问题 I'm trying to find the shared elements (and the shared number of occurrences) between two lists. For example, the intersection of these two lists: a = [1, 1, 2, 3, 4, 5, 6, 7, 8, 1] b = [1, 1, 3, 5, 7, 9] should return Counter({1: 2, 3: 1, 5: 1, 7: 1}) or something similar, e.g. {1: 2, 3: 1, 5: 1, 7: 1} or [1, 1, 3, 5, 7] (order of the list doesn't matter). I already have an approach that works: cnts_a = Counter(a) cnts_b = Counter(b) cnts_a_b = Counter() # counter for the shared values for

问题 Let's say I have a string and a list of strings: a = 'ABCDEFG' b = ['ABC', 'QRS', 'AHQ'] How can I pull out the string in list b that matches up perfectly with a section of the string a? So the would return would be something like ['ABC'] The most important issue is that I have tens of millions of strings, so that time efficiency is essential. 回答1: If you only want the first match in b: next((s for s in b if s in a), None) This has the advantage of short-circuiting as soon as it finds a match

问题 I was wondering how I would go about mapping 2D screen coordinates to a 3D world (specifically the xz plane) knowing: -position of the camera -equation of the screen plane -equation of the xz plane All I want to do is have the land on the xz plane light up when I hover the mouse over it. Any help is greatly appreciated! Thanks! 回答1: If your world is rotated and shifted such that the camera is at x=y=z=0 (world coordinates), the world z coordinate increases away from the viewer (into the

问题 I was wondering how I would go about mapping 2D screen coordinates to a 3D world (specifically the xz plane) knowing: -position of the camera -equation of the screen plane -equation of the xz plane All I want to do is have the land on the xz plane light up when I hover the mouse over it. Any help is greatly appreciated! Thanks! 回答1: If your world is rotated and shifted such that the camera is at x=y=z=0 (world coordinates), the world z coordinate increases away from the viewer (into the