蟒蛇谷歌地球坐标距离计算

Question

嗨我有一个名为地标的kml文件和4个节点（地标）位于谷歌地球上的一个区域。每个地标节点都有一个经度和纬度。

<?xml version="1.0" encoding="UTF-8"?> 
<kml xmlns="http://www.opengis.net/kml/2.2" xmlns:gx="http://www.google.com/kml/ext/2.2" xmlns:kml="http://www.opengis.net/kml/2.2" xmlns:atom="http://www.w3.org/2005/Atom"> 
<Document> 
    <name>placemarks.kml</name> 
    <StyleMap id="m_ylw-pushpin"> 
     <Pair> 
      <key>normal</key> 
      <styleUrl>#s_ylw-pushpin</styleUrl> 
     </Pair> 
     <Pair> 
      <key>highlight</key> 
      <styleUrl>#s_ylw-pushpin_hl</styleUrl> 
     </Pair> 
    </StyleMap> 
    <Style id="s_ylw-pushpin_hl"> 
     <IconStyle> 
      <scale>1.3</scale> 
      <Icon> 
       <href>http://maps.google.com/mapfiles/kml/pushpin/ylw-pushpin.png</href> 
      </Icon> 
      <hotSpot x="20" y="2" xunits="pixels" yunits="pixels"/> 
     </IconStyle> 
    </Style> 
    <Style id="s_ylw-pushpin"> 
     <IconStyle> 
      <scale>1.1</scale> 
      <Icon> 
       <href>http://maps.google.com/mapfiles/kml/pushpin/ylw-pushpin.png</href> 
      </Icon> 
      <hotSpot x="20" y="2" xunits="pixels" yunits="pixels"/> 
     </IconStyle> 
    </Style> 
    <Folder> 
     <name>placemarks</name> 
     <open>1</open> 
     <Placemark> 
      <name>node0</name> 
      <LookAt> 
       <longitude>21.78832062146911</longitude> 
       <latitude>38.28791526390673</latitude> 
       <altitude>0</altitude> 
       <heading>0.001539813336055052</heading> 
       <tilt>44.99941206765101</tilt> 
       <range>990.2435222326291</range> 
       <gx:altitudeMode>relativeToSeaFloor</gx:altitudeMode> 
      </LookAt> 
      <styleUrl>#m_ylw-pushpin</styleUrl> 
      <Point> 
       <coordinates>21.78400936610002,38.2874355527483,67.51641688336248</coordinates> 
      </Point> 
     </Placemark> 
     <Placemark> 
      <name>node1</name> 
      <LookAt> 
       <longitude>21.78832062146911</longitude> 
       <latitude>38.28791526390673</latitude> 
       <altitude>0</altitude> 
       <heading>0.001539813336055052</heading> 
       <tilt>44.99941206765101</tilt> 
       <range>990.2435222326291</range> 
       <gx:altitudeMode>relativeToSeaFloor</gx:altitudeMode> 
      </LookAt> 
      <styleUrl>#m_ylw-pushpin</styleUrl> 
      <Point> 
       <coordinates>21.78453228393861,38.28690995466475,67.51641688336248</coordinates> 
      </Point> 
     </Placemark> 
     <Placemark> 
      <name>node2</name> 
      <LookAt> 
       <longitude>21.78832062146911</longitude> 
       <latitude>38.28791526390673</latitude> 
       <altitude>0</altitude> 
       <heading>0.001539813336055052</heading> 
       <tilt>44.99941206765101</tilt> 
       <range>990.2435222326291</range> 
       <gx:altitudeMode>relativeToSeaFloor</gx:altitudeMode> 
      </LookAt> 
      <styleUrl>#m_ylw-pushpin</styleUrl> 
      <Point> 
       <coordinates>21.7848823502596,38.2869152766261,67.51641688336248</coordinates> 
      </Point> 
     </Placemark> 
     <Placemark> 
      <name>node3</name> 
      <LookAt> 
       <longitude>21.78832062146911</longitude> 
       <latitude>38.28791526390673</latitude> 
       <altitude>0</altitude> 
       <heading>0.001539813336055052</heading> 
       <tilt>44.99941206765101</tilt> 
       <range>990.2435222326291</range> 
       <gx:altitudeMode>relativeToSeaFloor</gx:altitudeMode> 
      </LookAt> 
      <styleUrl>#m_ylw-pushpin</styleUrl> 
      <Point> 
       <coordinates>21.78459887820567,38.28740826552452,67.51641688336248</coordinates> 
      </Point> 
     </Placemark> 
    </Folder> 
</Document> 
</kml> 

我要的是计算NODE0和node2,3,4之间的距离......（保持不变NODE0在距离函数），然后打印结果。

通过使用下面的代码：（我需要对其进行修改，以便有下面的输出）

# adapted from haversine.py <https://gist.github.com/rochacbruno/2883505> 
    # see also <http://en.wikipedia.org/wiki/Haversine_formula> 
    from math import atan2, cos, sin, sqrt, radians 

    def calc_distance(origin, destination): 
     """great-circle distance between two points on a sphere 
      from their longitudes and latitudes""" 
     lat1, lon1 = origin 
     lat2, lon2 = destination 
     radius = 6371 # km. earth 

     dlat = radians(lat2-lat1) 
     dlon = radians(lon2-lon1) 
     a = (sin(dlat/2) * sin(dlat/2) + cos(radians(lat1)) * cos(radians(lat2)) * 
      sin(dlon/2) * sin(dlon/2)) 
     c = 2 * atan2(sqrt(a), sqrt(1-a)) 
     d = radius * c 

     return d 

    from xml.dom import minidom 

    xmldoc = minidom.parse("placemarks.kml") 
    kml = xmldoc.getElementsByTagName("kml")[0] 
    document = kml.getElementsByTagName("Document")[0] 
    placemarks = document.getElementsByTagName("Placemark") 

    nodes = {} 
    for placemark in placemarks: 
     nodename = placemark.getElementsByTagName("name")[0].firstChild.data[:-1] 
     coords = placemark.getElementsByTagName("coordinates")[0].firstChild.data 
     lst1 = coords.split(",") 
     longitude = float(lst1[0]) 
     latitude = float(lst1[1]) 
     nodes[nodename] = (latitude, longitude) 

昂得到这样的输出：

node1: (21.78453228393861, 38.28690995466475), distance from node0: 
node2: (21.78488235025960, 38.28691527662610), distance from node0: 
node3: (21.78459887820567, 38.28740826552452), distance from node0: 

Answer 1

在你收集代码从KML文件中提取的节点和从XML中提取节点的节点名称始终相同，因此当您尝试将其存储在字典nodes中时，最终只能得到一个点。这里是一个修正后的脚本（仅最后一部分，需要加以固定），我认为没有你需要什么（请告诉我们，如果不是这种情况，你需要别的东西）：

nodes = {} 
for placemark in placemarks: 
    nodename = placemark.getElementsByTagName("name")[0].firstChild.data 
    coords = placemark.getElementsByTagName("coordinates")[0].firstChild.data 
    lst1 = coords.split(",") 
    longitude = float(lst1[0]) 
    latitude = float(lst1[1]) 
    nodes[nodename] = (latitude, longitude) 

for n in nodes: 
    if n == 'node0': 
     continue 
    print n, nodes[n], 'distance from node0:', calc_distance(nodes['node0'], nodes[n]) 

这里是输出：

node1 (38.28690995466475, 21.78453228393861) distance from node0: 0.074152874049 
node3 (38.28740826552452, 21.78459887820567) distance from node0: 0.0515409901388 
node2 (38.2869152766261, 21.7848823502596) distance from node0: 0.0956671636024