distance

问题 I want to compute the Zhang-Shasha tree-edit distance between 2 trees ( zss library). However, my trees are in the form of networkx graphs (they actually represent DOM html trees). The example in the zss documentation shows how to create a tree by hand: from zss import * A = ( Node("f") .addkid(Node("a") .addkid(Node("h")) .addkid(Node("c") .addkid(Node("l")))) .addkid(Node("e")) ) zss.simple_distance(A, A) # [0.0] Which would be the same tree as: import networkx as nx G=nx.DiGraph() G.add

问题 I have already been facing issues in meteor when dealing with reactive sorting of a publication according to various data. Every time, I never found a real answer to what I was trying to achieve and I ended up giving up and just deciding "not to build my app that way", which always makes me really sad. Now maybe I can phrase this problem simply enough that it could get a constructive and very interesting answer. I think it sounds like it should be possible to be done in a Meteor app, so here

问题 Given a starting point, a heading, a distance, and a line segment, find the first point along this heading that is the specified distance away from this line segment. I covered two cases, but I haven't been able to cover the last one. First case: heading away from the line. Ignore it even if the starting point is within the specified distance. Second case: It intersects the line. I solved it using trig and triangles. Initially didn't consider the next case. Third case: It is heading towards

问题 i want to get total duration and distance between two location along with waypoints. the methodwhich i'm using is giving me distance and duration but without waypoints. so can any one help me? my method look like below... public String getDistance(final double lat1, final double lon1, final double lat2, final double lon2){ Thread thread=new Thread(new Runnable() { @Override public void run() { try { URL url = new URL("https://maps.googleapis.com/maps/api/directions/json?origin=" + lat1 + ","

问题 I have two datasets (csv format) of different lengths, both containing addresses as well as coordinates (log and lat). The both have this shape (example Dataset A): ID Address lat long 1 Lausitzer Strasse, 20/22, 2991, Lauta, Germany 51.46228 14.09522 2 Parkstrasse, 6, 2991, Lauta, Germany 51.4631141 14.1109184 3 Parkstrasse, 6, 2991, Lauta , Germany 51.4631141 14.1109184 4 Arndtstrasse, 27, 2991, Lauta, Germany 51.44664 14.10287 5 Goethestrasse, 13, 4746, Hartha, Germany 51.0965679 12

问题 I'm attempting to find the euclidean distance in meters between two points on an MKMapView using iPhone OS 3.2. The problem is that I have these coordinates in terms of latitude and longitude, which, mathematically provides me enough data to find the distance, but it's going to take some tricky trigonometry. Is there any simpler solution? Thanks! 回答1: CLLocation has a method to calculate the distance for you: - (CLLocationDistance)distanceFromLocation:(const CLLocation *)location API docs

问题 I have three coordinates (lat,lon) on a sphere. If you would rotate the whole sphere from coord1 to coord2, where will coord3 now be located? I've been trying this out in Python using Great Circle (http://www.koders.com/python/fid0A930D7924AE856342437CA1F5A9A3EC0CAEACE2.aspx?s=coastline) but I create strange results as the newly calculated points all group together at the equator. That must have something to do with the azimuth calculation I assume? Does anyone maybe know how to calculate

问题 I have a very large csv file (about 91 million rows so a for loop takes too long in R) of similarities between keywords (about 50,000 unique keywords) that when I read into a data.frame looks like: > df kwd1 kwd2 similarity a b 1 b a 1 c a 2 a c 2 It is a sparse list and I can convert it into a sparse matrix using sparseMatrix(): > myMatrix a b c a . 1 2 b 1 . . c 2 . . However, now I would like to convert this into a dist object. I tried as.dist(myMatrix) but I was given the error that the

问题 I'm using postgresql as db , i have the table named car_wash with field "point geometry"(use postgis) so in application I'm getting lon lat from user using GOOGLE API, next step I need to create circle around user and check if car_wash inside this circle I use select * from car_wash cw where ST_DWithin ( cw.lon_lat, ST_GeomFromText('POINT(54.21 22.54)') )=false AND not cw.was_deleted Is it corect way? IF you need my srid is 0 according to this query Select Find_SRID('public', 'car_wash', 'lon

问题 My Profile model has this field: location = models.PointField(geography=True, dim=2, srid=4326) I'd like to calculate the distance between the two of these locations (taking into account that the Earth is a spheroid) using GeoDjango, so that I can store this distance in the database. How can I calculate this distance with GeoDjango? What units are the results in? Is there a 'best' way to store this data? Float? Decimal? I've reviewed previous, similar questions, and haven't found them useful.