Question

我这里有一份文件如下：

FICN10 CWIS 211446
ICEBERG BULLETIN FOR THE EAST COAST WATERS ISSUED BY ENVIRONMENT
CANADA AT 11:00 A.M. EDT TUESDAY 21 OCTOBER 2014 FOR TODAY.
THE NEXT SCHEDULED BULLETIN WILL BE ISSUED AT 11:00 A.M. WEDNESDAY.
ICEBERG LIMIT AT 0000 UTC 22 OCT ESTIMATED FROM NEWFOUNDLAND NEAR
4900N 5350W TO 4830N 4900W TO 5000N 4900W TO 6000N 5830W TO
6000N 4000W TO 3000N 5000W.

我正在尝试使用perl脚本，在其中我可以将坐标转换为如下所示的csv文件：

4900N 5350W 
4830N 4900W
5000N 4900W
6000N 5830W
6000N 4000W
3000N 5000W

我有一段代码，其中我试图这样做，因为我没有得到预期的结果：

您能看一下代码，看看应该做些什么才能将文本文件中的所有坐标转换成上述格式？

以下是代码：

`rm -f coords.TXT`;
open FPOUT, ">$outfile" or die "\nERROR: Could create/write $outfile\n\n";
for ( $ii = 0; $ii < 7; $ii++ ) {
    #if ($ii==5)
    #{
    #   print STDOUT "LINE 1\n";
    #}
    #if ($ii==6)
    #{
    #   print STDOUT "LINE 2\n";
    #}
    @words = split " ", "$inline[$ii]";
    for ( $jj = 0; $jj < (@words); $jj++ ) {
        @char = split "", "$words[$jj]";
        $n = 0;
        for ( $kk = 0; $kk < (@char); $kk++ ) {
            $n = $n + 1;
        }
        if ( $n =~ 5 or $n =~ 6 ) {
            if ( $char[0] =~ /[a-zA-z]/ ) {

            } else {
                if ( $char[4] =~ "W" or $char[4] =~ "E" or $char[4] =~ "N" or $char[4] =~ "S" ) {
                    if ( $n =~ 6 ) {
                        if ( $char[5] =~ "." ) {
                            $words[$jj] =~ s/\.//;
                        }
                    }
                    if ( $char[4] =~ "W" or $char[4] =~ "E" ) {
                        $lon = $words[$jj];
                        print STDOUT "longitude is $lon\n";
                    } elsif ( $char[4] =~ "N" or $char[4] =~ "S" ) {
                        $lat = $words[$jj];
                        print STDOUT "Latitude is $lat\n";

                    }
                    print FPOUT "$lat $lon\n";
                }

            }
        }

    }
}

close FPOUT;

Answer 1

使用正则表达式解析数据

要提取所需的模式，您只需要一个正则表达式：

while (<DATA>) {
    print "$_\n" for /\b\d+[NS]\s+\d+[WE]\b/g;
}

__DATA__
FICN10 CWIS 211446
ICEBERG BULLETIN FOR THE EAST COAST WATERS ISSUED BY ENVIRONMENT
CANADA AT 11:00 A.M. EDT TUESDAY 21 OCTOBER 2014 FOR TODAY.
THE NEXT SCHEDULED BULLETIN WILL BE ISSUED AT 11:00 A.M. WEDNESDAY.
ICEBERG LIMIT AT 0000 UTC 22 OCT ESTIMATED FROM NEWFOUNDLAND NEAR
4900N 5350W TO 4830N 4900W TO 5000N 4900W TO 6000N 5830W TO
6000N 4000W TO 3000N 5000W.

输出：

4900N 5350W
4830N 4900W
5000N 4900W
6000N 5830W
6000N 4000W
3000N 5000W

Mark Setchell

的文件处理

有关如何使用Perl处理文件的一些示例，我建议您查看：perlfaq5 - How do I change, delete, or insert a line in a file, or append to the beginning of a file?

在您的具体情况下，可能会使用以下内容：

#!/usr/bin/env perl
use strict;
use warnings;
use autodie;

my $file = 'bulletin.txt';

open my $fh, "<", $file;

while (<$fh>) {
    print "$_\n" for /\b\d+[NS]\s+\d+[WE]\b/g;
}

用perl解析纬度和经度

1 个答案:

使用正则表达式解析数据

Mark Setchell