Question

我正在处理大文件。我想知道，在你看来，当你想知道$ file1中的单词“x”是否存在于file2的句子“y”中时，处理大文件的最佳方法是什么。我的文件有超过20000行..

示例：

这是第一个文件的内容：

eat
take
breath
you
alpha

这是第二个文件的内容：

eat,hungry
love,lovers
me,mine
take,taken,give
you,u,yo
fun,funny

这是我可能期望的第三个文件的内容

eat : eat,hungry
take : take,taken,give
you : you,u,yo

你可以看到，我想在第一个文件的第二个文件中找到匹配的表达式。

我的解决方案 - 但循环永远不会结束 -

解决方法1：

$file1= "words.txt";
$file2 = "expressions.txt";
$out = "out.txt";

open (W, "<", $file1);
open (E, "<", $file2);
open (OUT, ">", $out);

while(defined($l = <W>)){
    @a = split (/\n/, $l);
    push @w, @a;
}

while(defined($l2 = <E>)){
    for ($i = 0; $i < @w; $i++){
        if (grep /\Q\b$w[$i]\b\E/, $l2){ #or just /\b$w[$i]\b/
            print OUT "$w[$i] : $l2\n";
        }
    }
}

溶液2：

$file1= "words.txt";
$file2 = "expressions.txt";
$out = "out.txt";

open (W, "<", $file1);
open (E, "<", $file2);
open (OUT, ">", $out);

while(defined($l = <W>)){
    @a = split (/\n/, $l);
    push @w, @a;

while(defined($l2 = <E>)){
    @b = split (/\n/, $l2);
    push @e, @b;
}

for ($k = 0; $k < @e; $k++){
    for ($i = 0; $i < @w; $i++){
        if (grep /\b$w[$i]\b/, $e[$k]){
            print OUT "$w[$i] : $w[$l]\n";
        }
    }
}

Answer 1

如何首先处理表达式文件以使字典将每个单词映射到一个句子，然后查找words.txt中的单词是否在字典中？我想这可能会更快。源代码如下：

#! /opt/VRTSperl/bin/perl

    $words = "words.txt";
    $expressions = "expressions.txt";
    $out = "out.txt";

    open (E, "<", $expressions);
    open (W, "<", $words);
    open (OUT, ">", $out);

    my %dic;

    while (my $sentence = <E>) {
        chomp($sentence);
        my @words = split(/,/, $sentence);
        foreach my $word (@words) {
            $dic{$word} .= "$sentence";
        }   
    }

    while (my $word = <W>) {
        chomp($word);
        if ($dic{$word}) {
            print OUT "$word : $dic{$word}\n"
        }   
    }

Answer 2

#!/usr/local/bin/perl
use strict;
use warnings;
open (my $fh, "<", "f1.txt") or die $!;
open (my $fh2, "<", "f2.txt") or die $!;
my @keys;
while(chomp(my $line = <$fh>)){
        push @keys, $line;
}
while(chomp(my $line2 = <$fh2>)){
        foreach (@keys){
                if ($line2 =~ $_){
                        print "$_ : $line2\n";
                }
        }
}

输出

eat : eat,hungry
take : take,taken,give
you : you,u,yo

Answer 3

您尝试匹配文字\b而不是字边界，所以

/\Q\b$w[$i]\b\E/

实际应该是

/\b\Q$w[$i]\E\b/

Perl - 如何处理搜索相似单词的大文件

3 个答案: