我是python的新手。我有这个非常大的xml文件，我想从中提取一些数据。这是一段摘录：
<program>
<id>38e072a7-8fc9-4f9a-8eac-3957905c0002</id>
<programID>3853</programID>
<orchestra>New York Philharmonic</orchestra>
<season>1842-43</season>
<concertInfo>
<eventType>Subscription Season</eventType>
<Location>Manhattan, NY</Location>
<Venue>Apollo Rooms</Venue>
<Date>1842-12-07T05:00:00Z</Date>
<Time>8:00PM</Time>
</concertInfo>
<worksInfo>
<work ID="52446*">
<composerName>Beethoven, Ludwig van</composerName>
<workTitle>SYMPHONY NO. 5 IN C MINOR, OP.67</workTitle>
<conductorName>Hill, Ureli Corelli</conductorName>
</work>
<work ID="8834*4">
<composerName>Weber, Carl Maria Von</composerName>
<workTitle>OBERON</workTitle>
<movement>"Ozean, du Ungeheuer" (Ocean, thou mighty monster), Reiza (Scene and Aria), Act II</movement>
<conductorName>Timm, Henry C.</conductorName>
<soloists>
<soloist>
<soloistName>Otto, Antoinette</soloistName>
<soloistInstrument>Soprano</soloistInstrument>
<soloistRoles>S</soloistRoles>
</soloist>
</soloists>
</work>
<work ID="3642*">
<composerName>Hummel, Johann</composerName>
<workTitle>QUINTET, PIANO, D MINOR, OP. 74</workTitle>
<soloists>
<soloist>
<soloistName>Scharfenberg, William</soloistName>
<soloistInstrument>Piano</soloistInstrument>
<soloistRoles>A</soloistRoles>
</soloist>
<soloist>
<soloistName>Hill, Ureli Corelli</soloistName>
<soloistInstrument>Violin</soloistInstrument>
<soloistRoles>A</soloistRoles>
</soloist>
<soloist>
<soloistName>Derwort, G. H.</soloistName>
<soloistInstrument>Viola</soloistInstrument>
<soloistRoles>A</soloistRoles>
</soloist>
<soloist>
<soloistName>Boucher, Alfred</soloistName>
<soloistInstrument>Cello</soloistInstrument>
<soloistRoles>A</soloistRoles>
</soloist>
<soloist>
<soloistName>Rosier, F. W.</soloistName>
<soloistInstrument>Contrabass</soloistInstrument>
<soloistRoles>A</soloistRoles>
</soloist>
</soloists>
</work>
<work ID="0*">
<interval>Intermission</interval>
</work>
<work ID="8834*3">
<composerName>Weber, Carl Maria Von</composerName>
<workTitle>OBERON</workTitle>
<movement>Overture</movement>
<conductorName>Etienne, Denis G.</conductorName>
</work>
<work ID="8835*1">
<composerName>Rossini, Gioachino</composerName>
<workTitle>ARMIDA</workTitle>
<movement>Duet</movement>
<conductorName>Timm, Henry C.</conductorName>
<soloists>
<soloist>
<soloistName>Otto, Antoinette</soloistName>
<soloistInstrument>Soprano</soloistInstrument>
<soloistRoles>S</soloistRoles>
</soloist>
<soloist>
<soloistName>Horn, Charles Edward</soloistName>
<soloistInstrument>Tenor</soloistInstrument>
<soloistRoles>S</soloistRoles>
</soloist>
</soloists>
</work>
<work ID="8837*6">
<composerName>Beethoven, Ludwig van</composerName>
<workTitle>FIDELIO, OP. 72</workTitle>
<movement>"In Des Lebens Fruhlingstagen...O spur ich nicht linde," Florestan (aria)</movement>
<conductorName>Timm, Henry C.</conductorName>
<soloists>
<soloist>
<soloistName>Horn, Charles Edward</soloistName>
<soloistInstrument>Tenor</soloistInstrument>
<soloistRoles>S</soloistRoles>
</soloist>
</soloists>
</work>
<work ID="8336*4">
<composerName>Mozart, Wolfgang Amadeus</composerName>
<workTitle>ABDUCTION FROM THE SERAGLIO,THE, K.384</workTitle>
<movement>"Ach Ich liebte," Konstanze (aria)</movement>
<conductorName>Timm, Henry C.</conductorName>
<soloists>
<soloist>
<soloistName>Otto, Antoinette</soloistName>
<soloistInstrument>Soprano</soloistInstrument>
<soloistRoles>S</soloistRoles>
</soloist>
</soloists>
</work>
<work ID="5543*">
<composerName>Kalliwoda, Johann W.</composerName>
<workTitle>OVERTURE NO. 1, D MINOR, OP. 38</workTitle>
<conductorName>Timm, Henry C.</conductorName>
</work>
</worksInfo>
</program>
<program>
我想要做的是提取以下信息：programID，orchestra，season，eventType，work ID，soloistName，solositInstrument，soloistRole
以下是我正在使用的代码：
import csv
import xml.etree.cElementTree as ET
tree = ET.iterparse('complete.xml.txt')
#root = tree.getroot()
for program in root.iter('program'):
ID = program.findtext('id')
programID = program.findtext('programID')
orchestra = program.findtext('orchestra')
season = program.findtext('season')
for concert in program.findall('concertInfo'):
event = concert.findtext('eventType')
for worksInfo in program.findall('worksInfo'):
for work in worksInfo.iter('work'):
workid = work.get('ID')
for soloists in work.iter('soloists'):
for soloist in soloists.iter('soloist'):
soloname = soloist.findtext('soloistName')
soloinstrument = `soloist.findtext('soloistInstrument')`
solorole = soloist.findtext('soloistRoles')
#print(soloname, soloinstrument, solorole)
#print(workid)
#print(event)
#print(programID , " , " , orchestra , " , " , season)
with open("nyphil.txt","a") as nyphil:
nyphilwriter = csv.writer(nyphil)
nyphilwriter.writerow([programID, orchestra, season, event, workid, `soloname.encode('utf-8'), soloinstrument, solorole])
nyphil.close()
当我运行此代码时，我只获得最后一个soloistName和soloistInstrumet。我想到的结果有点像每个程序的重复观察。所以我有类似的东西：
13918，纽约爱乐乐团，1842-43，订阅季，52446 *，奥托，安托瓦内特，女高音，S
13918，....，3642 *，Scharfenberg，William，Piano，A
13918，....，3642 *，Hill，Ureli Corelli，Violin，A
等等，直到上一个工作ID：
13918，....，8336 * 4，Otto，Antoinette，Soprano，S
我得到的只是最后的工作：
13918，纽约爱乐乐团，1842-43，订阅季，8336 *，奥托，安托瓦内特，女高音，S
在文件中有超过15,000个程序，例如我发布的示例。我想解析所有这些并提取上面提到的信息。我不完全确定如何去做这件事，我已经在互联网上寻找一种方法来做到这一点，但我尝试的一切都不起作用！
答案 0 :(得分：0)
你的问题是你误解了循环的工作方式。具体来说，这些值只会在您进入循环时发生变化：
for x in range(10):
pass
print(x) # prints 9
VS
for x in range(10):
print(x)
这是两件不同的事情。你在做前者。你需要做的是这样的事情：
with open('nyphil.txt', 'w') as f:
nyphilwriter = csv.writer(f)
for program in root.iter('program'):
id_ = program.findtext('id')
program_id = program.findtext('programID')
orchestra = program.findtext('orchestra')
season = program.findtext('season')
for concert in program.findall('concertInfo'):
event = concert.findtext('eventType')
for info in program.findall('worksInfo'):
for work in info.iter('work'):
work_id = work.get('ID')
for soloists in work.iter('soloists'):
for soloist in soloists.iter('soloist'):
# Change this line to whatever you want to write out
nyphilwriter.writerow([id, program_id, orchestra, season, event, work_id, soloist.findtext('soloistName')])