swift - 将段落拆分成句子

Question

我有一大堆文字。例如

I want to split a paragraph into sentences. But, there is a problem. My paragraph includes dates like Jan.13, 2014 , words like U.A.E and numbers like 2.2. How do i split this.**

输出:

I want to split a paragraph into sentences.

But, there is a problem.

My paragraph includes dates like Jan.13, 2014 , words like U.A.E and numbers like 2.2.

How do i split this.

这是我想要的输出。谁能指导我在 Swift 中做到这一点。

谢谢。

Answer 1

使用 NSLinguisticTagger。它会根据您给定的输入得到正确的句子，因为它会根据实际的语言术语进行分析。

这是一个粗略的草稿(Swift 1.2，它不会在 Swift 2.0 中编译):

let s = "I want to split a paragraph into sentences. But, there is a problem. My paragraph includes dates like Jan.13, 2014 , words like U.A.E and numbers like 2.2. How do i split this."
var r = [Range<String.Index>]()
let t = s.linguisticTagsInRange(
    indices(s), scheme: NSLinguisticTagSchemeLexicalClass,
    options: nil, tokenRanges: &r)
var result = [String]()
let ixs = Array(enumerate(t)).filter {
    $0.1 == "SentenceTerminator"
    }.map {r[$0.0].startIndex}
var prev = s.startIndex
for ix in ixs {
    let r = prev...ix
    result.append(
        s[r].stringByTrimmingCharactersInSet(
             NSCharacterSet.whitespaceCharacterSet()))
    prev = advance(ix,1)
}

这是一个 Swift 2.0 版本(更新到 Xcode 7 beta 6):

let s = "I want to split a paragraph into sentences. But, there is a problem. My paragraph includes dates like Jan.13, 2014 , words like U.A.E and numbers like 2.2. How do i split this."
var r = [Range<String.Index>]()
let t = s.linguisticTagsInRange(
    s.characters.indices, scheme: NSLinguisticTagSchemeLexicalClass,
    tokenRanges: &r)
var result = [String]()
let ixs = t.enumerate().filter {
    $0.1 == "SentenceTerminator"
}.map {r[$0.0].startIndex}
var prev = s.startIndex
for ix in ixs {
    let r = prev...ix
    result.append(
        s[r].stringByTrimmingCharactersInSet(
            NSCharacterSet.whitespaceCharacterSet()))
    prev = ix.advancedBy(1)
}

此处针对 Swift 3 进行了更新:

let s = "I want to split a paragraph into sentences. But, there is a problem. My paragraph includes dates like Jan.13, 2014 , words like U.A.E and numbers like 2.2. How do i split this."
var r = [Range<String.Index>]()
let t = s.linguisticTags(
    in: s.startIndex..<s.endIndex,
    scheme: NSLinguisticTagSchemeLexicalClass,
    tokenRanges: &r)
var result = [String]()
let ixs = t.enumerated().filter {
    $0.1 == "SentenceTerminator"
    }.map {r[$0.0].lowerBound}
var prev = s.startIndex
for ix in ixs {
    let r = prev...ix
    result.append(
        s[r].trimmingCharacters(
            in: NSCharacterSet.whitespaces))
    prev = s.index(after: ix)
}

result 是一个包含四个字符串的数组，每个字符串一个句子:

["I want to split a paragraph into sentences.", 
 "But, there is a problem.", 
 "My paragraph includes dates like Jan.13, 2014 , words like U.A.E and numbers like 2.2.", 
 "How do i split this."]