在perl中分割包含经度或纬度表达式的字符串 [英] Splitting a string containing a longitude or latitude expression in perl

问题描述

我从包含真实测地线表达式的网络中检索数据，即我用Unicode符号U+00B0, U+2032 and U+2033表示度，分和秒，分别命名为度，素数和双素数.示例:

I retrieve data from the net containing real geodesic expressions, by that I mean degrees, minutes and seconds with Unicode symbols: U+00B0, U+2032 and U+2033, named Degree, Prime and Double Prime. Example:

my $Lat = "48° 25′ 43″ N";

我的目标是首先将这样的表达式转换为度，然后转换为弧度，以在我正在编写的Perl模块中使用，该模块实现了Vincenty逆公式来计算椭球大圆距离.我所有的代码目标都已达到伪大地测量学的要求，例如"48:25:43 N"，但是，当然，这是手工输入的测试数据，而不是真实世界的数据.我正在努力制作一个正则表达式，该正则表达式可以像现在处理伪数据一样拆分此真实数据，如下所示:

My objective is to convert such an expression first to degrees and then to radians to be used in a Perl module I am writing that implements the Vincenty inverse formula to calculate ellipsoidal great-circle distances. All my code objectives have been met with pseudo geodesics, such as "48:25:43 N", but of course, this is hand entered test data, not real world data. I am struggling with crafting a regular expression that can split this real data as I now do pseudo data, as in:

my ($deg, $min, $sec, $dir) = split(/[\s:]+/, $_[0], 4); # this works

我尝试了很多正则表达式，包括

I have tried many regular expressions including

/[°′″\s]+/ and
/[\x{0B00}\x{2032}\x{2033}\s]/+

所有结果令人沮丧，例如$deg = "48?", $min = "?", $sec = "25′43″ N" and $dir = undef.我已经将代码封装在大括号{}中，并使用utf8包含在该范围内；并使用功能'unicode_strings';都具有nada结果.

all with dismal results, such as $deg = "48?", $min = "?", $sec = "25′43″ N" and $dir = undef. I've encapsulated the code inside braces {} and included within that scope use utf8; and use feature 'unicode_strings'; all with nada results.

输入数据示例:

my $Lat = "48° 25′ 43″ N"; 

预期输出:

$deg = 48, $min = 25, $sec = 43 and $dir = "N"

推荐答案

您可以尝试使用此正则表达式来拆分字符串:

You may try this regex to split the string:

[^\dNSEW.]+

正则表达式演示

示例来源:( 在此处运行)

my $str = '48° 25′ 43″ N';
my $regex = qr/[^\dNSEW.]+/p;
my ($deg, $min, $sec, $dir) = split $regex, $str;

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