在寻找构建更好的地址定位器来处理单个字段地址表的方法时,我遇到了 Pyparsing 模块。在 Examples 页面上有一个名为“streetAddressParser”(作者未知)的脚本,我已将其完整复制在下面。虽然我已经阅读了文档并查看了 O'Reilly Recursive Decent Parser 教程,但我仍然对该地址解析器的代码感到困惑。我知道这个解析器仅代表地址定位器应用程序的一个组件,但我的 Python 经验仅限于 GIS 脚本编写,并且我很难理解此代码的某些部分。
首先,将数字定义为“零一二三...十一十二十三...十二十三十...”的目的是什么?如果我们知道地址字段以代表街道号码的整数开头,为什么不将其提取为第一个标记呢?
第二,为什么这个脚本使用了这么多位运算符(^、|、~)?这是因为性能提升还是因为 Pyparsing 模块中的处理方式不同?可以使用其他运算符代替它们并产生相同的结果吗?
我感谢您提供的任何指导,也感谢您耐心阅读本文。 谢谢你!
from pyparsing import *
# define number as a set of words
units = oneOf("Zero One Two Three Four Five Six Seven Eight Nine Ten"
"Eleven Twelve Thirteen Fourteen Fifteen Sixteen Seventeen Eighteen Nineteen",
caseless=True)
tens = oneOf("Ten Twenty Thirty Forty Fourty Fifty Sixty Seventy Eighty Ninety",caseless=True)
hundred = CaselessLiteral("Hundred")
thousand = CaselessLiteral("Thousand")
OPT_DASH = Optional("-")
numberword = ((( units + OPT_DASH + Optional(thousand) + OPT_DASH +
Optional(units + OPT_DASH + hundred) + OPT_DASH +
Optional(tens)) ^ tens )
+ OPT_DASH + Optional(units) )
# number can be any of the forms 123, 21B, 222-A or 23 1/2
housenumber = originalTextFor( numberword | Combine(Word(nums) +
Optional(OPT_DASH + oneOf(list(alphas))+FollowedBy(White()))) +
Optional(OPT_DASH + "1/2")
)
numberSuffix = oneOf("st th nd rd").setName("numberSuffix")
streetnumber = originalTextFor( Word(nums) +
Optional(OPT_DASH + "1/2") +
Optional(numberSuffix) )
# just a basic word of alpha characters, Maple, Main, etc.
name = ~numberSuffix + Word(alphas)
# types of streets - extend as desired
type_ = Combine( MatchFirst(map(Keyword,"Street St Boulevard Blvd Lane Ln Road Rd Avenue Ave "
"Circle Cir Cove Cv Drive Dr Parkway Pkwy Court Ct Square Sq"
"Loop Lp".split())) + Optional(".").suppress())
# street name
nsew = Combine(oneOf("N S E W North South East West NW NE SW SE") + Optional("."))
streetName = (Combine( Optional(nsew) + streetnumber +
Optional("1/2") +
Optional(numberSuffix), joinString=" ", adjacent=False )
^ Combine(~numberSuffix + OneOrMore(~type_ + Combine(Word(alphas) + Optional("."))), joinString=" ", adjacent=False)
^ Combine("Avenue" + Word(alphas), joinString=" ", adjacent=False)).setName("streetName")
# PO Box handling
acronym = lambda s : Regex(r"\.?\s*".join(s)+r"\.?")
poBoxRef = ((acronym("PO") | acronym("APO") | acronym("AFP")) +
Optional(CaselessLiteral("BOX"))) + Word(alphanums)("boxnumber")
# basic street address
streetReference = streetName.setResultsName("name") + Optional(type_).setResultsName("type")
direct = housenumber.setResultsName("number") + streetReference
intersection = ( streetReference.setResultsName("crossStreet") +
( '@' | Keyword("and",caseless=True)) +
streetReference.setResultsName("street") )
streetAddress = ( poBoxRef("street")
^ direct.setResultsName("street")
^ streetReference.setResultsName("street")
^ intersection )
tests = """\
3120 De la Cruz Boulevard
100 South Street
123 Main
221B Baker Street
10 Downing St
1600 Pennsylvania Ave
33 1/2 W 42nd St.
454 N 38 1/2
21A Deer Run Drive
256K Memory Lane
12-1/2 Lincoln
23N W Loop South
23 N W Loop South
25 Main St
2500 14th St
12 Bennet Pkwy
Pearl St
Bennet Rd and Main St
19th St
1500 Deer Creek Lane
186 Avenue A
2081 N Webb Rd
2081 N. Webb Rd
1515 West 22nd Street
2029 Stierlin Court
P.O. Box 33170
The Landmark @ One Market, Suite 200
One Market, Suite 200
One Market
One Union Square
One Union Square, Apt 22-C
""".split("\n")
# how to add Apt, Suite, etc.
suiteRef = (
oneOf("Suite Ste Apt Apartment Room Rm #", caseless=True) +
Optional(".") +
Word(alphanums+'-')("suitenumber"))
streetAddress = streetAddress + Optional(Suppress(',') + suiteRef("suite"))
for t in map(str.strip,tests):
if t:
#~ print "1234567890"*3
print t
addr = streetAddress.parseString(t, parseAll=True)
#~ # use this version for testing
#~ addr = streetAddress.parseString(t)
print "Number:", addr.street.number
print "Street:", addr.street.name
print "Type:", addr.street.type
if addr.street.boxnumber:
print "Box:", addr.street.boxnumber
print addr.dump()
print
最佳答案
在某些地址中,主要号码被拼写为一个单词,正如您从测试中靠近列表末尾的几个地址中看到的那样。您的陈述“如果我们知道地址字段以代表街道号码的整数开头...”是一个大“如果”。很多很多地址不以数字开头。
按位运算符可能用于设置标志以将标记分类为具有某些属性。对于设置位/标志的目的,按位运算符非常高效且方便。
看到解析器尝试解析没有 using a regular expression 的街道地址,真是令人耳目一新。 ...另请参阅this page about some of the challenges of parsing freeform addresses .
但是,值得注意的是,这个解析器看起来会错过各种各样的地址。它似乎没有考虑犹他州、威斯康星州和农村地区常见的一些特殊地址格式。它还缺少大量辅助指示符和街道后缀。
关于python - 了解街道地址的 Pyparsing,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/23523365/