intersection

Are there any open source tools or libraries (ideally in python) that are available for performing lots of intersections with 3D geometry read from an ESRI shapefile? Most of the tests will be simple line segments vs polygons. I've looked into OGR 1.7.1 / GEOS 3.2.0, and whilst it loads the data correctly, the resulting intersections aren't correct, and most of the other tools available seem to build on this work. Whilst CGAL would have been an alternative, it's license isn't suitable. The Boost generic geometry library looks fantastic, but the api is huge, and doesn't seem to support wkt or

I'm currently determining which screen a window is on, by checking on which screen it's very left-top position is. Now I'd like to change that so that I can find out on which scren the most surface area of the window is to be found. Any ideas how that can be accomplished? Here is my old code: (it simply moves the active window between all available screens when pressing F1) F1:: WinGetPos, X, Y,,, A window := {x:X,y:Y} monitors := GetMonitors() Loop % monitors.MaxIndex() { curMonitor := monitors[A_Index] If IsPointInRectange(window,curMonitor) { nextMonitorIndex := (A_Index = monitors.MaxIndex

I've been using Redis for a while as a backend for Resque and now that I'm looking for a fast way to perform intersect operation on large sets of data, I decided to give Redis a shot. I've been conducting the following test: — x , y and z are Redis sets, they all contain approx. 1 million members (random integers taken from a seed array containing 3M+ members). — I want to intersect x y and z , so I'm using sintersectstore (to avoid overheating caused by data retrieval from the server to the client) sinterstore r x y z — the resulting set ( r ) contains about half a million members, Redis

So, I'd like to figure out a function that allows you to determine if two cubes of arbitrary rotation and size intersect. If the cubes are not arbitrary in their rotation (but locked to a particular axis) the intersection is simple; you check if they intersect in all three dimensions by checking their bounds to see if they cross or are within one another in all three dimensions. If they cross or are within in only two, they do not intersect. This method can be used to determine if the arbitrary cubes are even candidates for intersection, using their highest/lowest x, y, and z to create an

This seems simple but I can't quite figure it out. I have a curve calculated from x,y data. Then I have a line. I want to find the x, y values for where the two intersect. Here is what I've got so far. It's super confusing and doesn't give the correct result. I can look at the graph and find the intersection x value and calculate the correct y value. I'd like to remove this human step. import numpy as np import matplotlib.pyplot as plt from pylab import * from scipy import linalg import sys import scipy.interpolate as interpolate import scipy.optimize as optimize w = np.array([0.0, 11

I define intersection of two lists as follows: def intersect(a, b): return list(set(a) & set(b)) For three arguments it would look like: def intersect(a, b, c): return (list(set(a) & set(b) & set(c)) Can I generalize this function for variable number of lists? The call would look for example like: >> intersect([1, 2, 2], [2, 3, 2], [2, 5, 2], [2, 7, 2]) [2] EDIT: Python can only achieve it this way? intersect([ [1, 2, 2], [2, 3, 2], [2, 5, 2], [2, 7, 2] ]) [2] Use the * -list-to-argument operator and instead of your custom function use set.intersection : >>> lists = [[1, 2, 2], [2, 3, 2], [2,

I have two sets of n nodes. Now I want to connect each node from one set with another node from the other set. The resulting graph should have no intersections. I know of several sweep line algorithms ( Bentley-Ottmann-Algorithm to check where intersections occur, but I couldn't find an algorithm to solve those intersections, except for a brute-force approach. Each node from one set can be connected to any other node within the other set. Any pointers to (an efficient) algorithm that solves this problem? No implementation needed. EDIT1 : Here is one solution to the problem for n=7 : The black

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 key in set(cnts_a).intersection(cnts_b): cnts_a_b[key] = min(cnts_a[key], cnts_b[key]) But perhaps there