CODEWITHSUNDEEP
phpregexpreg-match
user2016210
user2016210

Reputation: 119

How do I limit the number of characters in a wildcard match in a preg_match pattern?

In the following snippet pre_match returns the first latitude reading followed by a great many characters then the longitude reading.
What I am after is the final latitude/longitude pair.
How do I limit the space between the two readings to a maximum of say 4 characters?
The .*? expression allows too many characters.
How might I change this to allow a smaller number?

<?php
$lcline="tuesday, 20th. light airs and clear weather. p.m. started at latitude 24 degrees 12 minutes took several azimuth, which gave the variation 16 degrees 30 minutes west. put the ship's company to three watches. wind variable; course south 21 degrees 30 minutes west; distance 28 miles; latitude 31 degrees 17 minutes, longitude 17 degrees 19 minutes west; at noon, funchall, island of madeira, north 13 degrees east, 76 miles. ";

preg_match('/(latitude\s+\d+\s+degrees\s+\d+\s+minutes.*?longitude\s+\d+\s+degrees\s+\d+\s+minutes)/', $lcline, $results);
echo "results=".$results[0]."<BR><BR>"
?>

Upvotes: 1

Views: 361

Answers (3)

elegisandi
elegisandi

Reputation: 474

If u say limit, you can use curly braces eg: /\s{4}/ this will select all with 4 white space characters consecutively

Upvotes: 0

Ehsan Chavoshi
Ehsan Chavoshi

Reputation: 725

Expression

Function

{n}

Match exactly n times, example:Click to test "\w{2}" equals "\w\w"; Click to test "a{5}" equals "aaaaa"

{m,n}

At least m but no more than n times: Click to test "ba{1,3}" matches "ba","baa","baaa"

{m,}

Match at least n times: Click to test "\w\d{2,}" matches "a12","_456","M12344"...

?

Match 1 or 0 times, equivalent to {0,1}: Click to test "a[cd]?" matches "a","ac","ad".

  • Match 1 or more times, equivalent to {1,}: Click to test "a+b" matches "ab","aab","aaab"...

Match 0 or more times, equivalent to {0,}: Click to test "\^*b" matches "b","^^^b"...

Reference : http://www.regexlab.com/en/regref.htm

Upvotes: 0

Toto
Toto

Reputation: 91385

Add .+ at the begining of the regex and get the result from group 1:

preg_match('/.+(latitude\s+\d+\s+degrees\s+\d+\s+minutes.*?longitude\s+\d+\s+degrees\s+\d+\s+minutes)/s', $lcline, $results);
echo "results=",$results[1],"\n";

Output:

results=latitude 31 degrees 17 minutes, longitude 17 degrees 19 minutes

Upvotes: 1

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