ich habe eine Frage zu einem Python Problem.
Ich möchte eine XML Datei mit einem Skript parsen.
Leider erhalte ich folgenden Fehler:
Ich habe heute schon den ganzen Tag gesucht - jedoch bin ich nicht fündig geworden.UnicodeEncodeError: 'ascii' codec can't encode character u'\xf6' in position 1: ordinal not in range(128)
Eine Testdatei zum Parsen findet man hier:
http://132.230.29.38/openlayer/convert/ ... 102007.osm
Hier noch der Code - vielleicht hat jemand einen Tipp für mich ?
Vielen Dank
brauns
Code: Alles auswählen
from xml.sax import make_parser, handler
from math import sqrt
from xml.sax.saxutils import escape
import osr
class OSMNode:
def __init__( self, id=None, geom=None, tags=None):
self.id = id
if tags is None:
self.tags = {}
else:
self.tags = tags
def __str__( self ):
return "%s, %s, %s" % (str(self.id), str(self.geom), str(self.tags))
class OSMWay:
def __init__( self, id=None, nodes=None, tags=None ):
self.id = id
if nodes is None:
self.nodes = []
else:
self.nodes = nodes
if tags is None:
self.tags = {}
else:
self.tags = tags
def __str__( self ):
return "%d, %s, %s" % ( self.id, str( self.nodes ), str(self.tags) )
class OSMFile:
class OSMHandler(handler.ContentHandler):
def __init__(self):
self._parent = None
self._curr_node = None
self._curr_way = None
self.nodes = {}
self.ways = {}
def startElement( self, name, attrs ):
if name == 'node':
self._parent = 'node'
self._curr_node = OSMNode()
self._curr_node.id = int( attrs['id'] )
self._curr_node.geom = ( float(attrs['lon']), float(attrs['lat']) )
if name == 'way':
self._parent = 'way'
self._curr_way = OSMWay()
self._curr_way.id = int( attrs['id'] )
if name == 'tag':
if self._parent == 'node':
self._curr_node.tags[ str(attrs['k']) ] = str(attrs['v'])
elif self._parent == 'way':
self._curr_way.tags[ str(attrs['k']) ] = str(attrs['v'])
if name == 'nd':
self._curr_way.nodes.append( int(attrs['ref']) )
def endElement( self, name ):
if name == 'node':
self.nodes[ self._curr_node.id ] = self._curr_node
self._curr_node == None
if name == 'way':
self.ways[ self._curr_way.id ] = self._curr_way
self._curr_way == None
def __init__( self, filename=None ):
# Set up member collections
self.nodes = {} #hash of id->(geom,tags)
self.ways = {} #hash of id->(nodes, tags)
if filename is not None:
self.parse_osmfile( filename )
def parse_osmfile( self, filename ):
osm_handler = OSMFile.OSMHandler()
parser = make_parser()
parser.setContentHandler(osm_handler)
parser.parse(filename)
self.nodes = osm_handler.nodes
self.ways = osm_handler.ways
def connected_nodes( self ):
"""Returns a list of all nodes that are referenced by more than one way"""
once = {}
twice = []
for id, parsedway in self.ways.iteritems():
for node in parsedway.nodes:
if node in once:
twice.append( node )
else:
once[node] = True
return twice
def split_way( self, way, split_nodes, top=True ):
if top:
id = way.id*1000 # open up a space for split id, but only if this is the first recusion level
else:
id = way.id
# Iterate down to the split point
i=1
for node in way.nodes[1:-1]: #don't want to split at the endpoints
if node in split_nodes:
#Split the Way at the splitpoint
left = OSMWay(id, way.nodes[:i+1], way.tags)
right = OSMWay(id+1, way.nodes[i:], way.tags)
# Recurse!
return [ left ] + self.split_way(right, split_nodes, top=False)
i = i+1
# Way was never split
return [ OSMWay(id, way.nodes, way.tags) ]
def split_ways( self ):
"""Returns osmfile object with split-up ways"""
split_ways = {}
split_nodes = self.connected_nodes()
for id, way in self.ways.iteritems():
xs = self.split_way( way, split_nodes )
for way in xs:
split_ways[way.id] = way
ret = OSMFile()
ret.nodes = self.nodes
ret.ways = split_ways
return ret
from_proj = osr.SpatialReference()
from_proj.SetWellKnownGeogCS( "EPSG:4326" )
to_proj = osr.SpatialReference()
to_proj.ImportFromProj4('+proj=merc')
tr = osr.CoordinateTransformation( from_proj, to_proj )
def project( self, point ):
pt = self.tr.TransformPoint( point[0], point[1] )
return (pt[1], pt[0])
def way_length( self, way_id ):
way = self.ways[way_id]
geom = [self.project( self.nodes[id][0] ) for id in way.nodes]
accum = 0
for i in range(0, len(geom)-1):
x1, y1 = geom[i]
x2, y2 = geom[i+1]
accum += sqrt( (x2-x1)**2 + (y2-y1)**2 )
return accum
def to_osm( self ):
ret = []
ret.append( "<?xml version='1.0' encoding='UTF-8'?>" )
ret.append( "<osm version='0.5' generator='libosm'>" )
for id, node in self.nodes.iteritems():
ret.append(" <node id='%d' visible='true' lat='%f' lon='%f'>"%(id, node.geom[1], node.geom[0]))
for k, v in node.tags.iteritems():
ret.append( " <tag k=\"%s\" v=\"%s\" />"%(k,escape(v)) )
ret.append(" </node>")
for id, way in self.ways.iteritems():
ret.append( " <way id='%d' visible='true'>"%id )
for node in way.nodes:
ret.append( " <nd ref='%d' />"%node )
for k, v in way.tags.iteritems():
ret.append( " <tag k=\"%s\" v=\"%s\" />"%(k,escape(v)) )
ret.append(" </way>")
ret.append( "</osm>" )
return "\n".join(ret)
if __name__ == '__main__':
print "Reading OSM file..."
osmfile = OSMFile( 'Freiburg_17102007.osm' )
print "Done"
print "%d nodes, %d ways" % (len(osmfile.nodes), len(osmfile.ways))
