您好我有一个名为Placemark的kml文件和位于Google地球上某个区域的4个节点（地标）。每个地标节点都有经度和纬度。
<?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>
我想要的是计算node0和node2,3,4之间的距离......（在距离函数中保持node0不变）然后打印结果。
使用以下代码:(我需要修改它以便输出如下）
# 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)
Ang获得如下输出：
node1: (21.78453228393861, 38.28690995466475), distance from node0:
node2: (21.78488235025960, 38.28691527662610), distance from node0:
node3: (21.78459887820567, 38.28740826552452), distance from node0:
答案 0 :(得分：0)
在收集从KML文件中提取的节点的代码中，当您从XML中提取节点时，节点的名称始终相同，因此当您尝试将其存储在字典nodes中时最后得到一点。这是一个经过修正的脚本（只有最后一部分，需要修复），我认为这是你所需要的（请告诉我们，如果不是这样，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