Latitude Longitude Regular Expression Validation PHP

latlong.php

<?php

/**
 * Validates a given latitude $lat
 *
 * @param float|int|string $lat Latitude
 * @return bool `true` if $lat is valid, `false` if not
 */
function validateLatitude($lat) {
  return preg_match('/^(\+|-)?(?:90(?:(?:\.0{1,6})?)|(?:[0-9]|[1-8][0-9])(?:(?:\.[0-9]{1,6})?))$/', $lat);
}

/**
 * Validates a given longitude $long
 *
 * @param float|int|string $long Longitude
 * @return bool `true` if $long is valid, `false` if not
 */
function validateLongitude($long) {
  return preg_match('/^(\+|-)?(?:180(?:(?:\.0{1,6})?)|(?:[0-9]|[1-9][0-9]|1[0-7][0-9])(?:(?:\.[0-9]{1,6})?))$/', $long);
}

/**
 * Validates a given coordinate
 *
 * @param float|int|string $lat Latitude
 * @param float|int|string $long Longitude
 * @return bool `true` if the coordinate is valid, `false` if not
 */
function validateLatLong($lat, $long) {
  return preg_match('/^[-]?(([0-8]?[0-9])\.(\d+))|(90(\.0+)?),[-]?((((1[0-7][0-9])|([0-9]?[0-9]))\.(\d+))|180(\.0+)?)$/', $lat.','.$long);
}


$tests = [
  'lat' => [
    '0.0','+90.0','-90.0','90.0','+45','-45','45','50','55.55','45,1','A',],
  'long' => [
    '0.0', '180', '-180', '+180', '179.9', 'A',
  ],
  'lat_long' => [
    '90.0,180.0',
    '47.1,179.1',
    '90.1a,180.1a'
  ]
];

echo "\033[37;44m:::::::::::: Tests ::::::::::::\033[0m".PHP_EOL;
echo "\033[1mType:\t\tValue:\tResult\033[0m".PHP_EOL;

foreach ($tests['lat'] as $lat) {
  echo "Latitude:\t$lat\t\t".((validateLatitude($lat)) ? "\033[32mMATCH\033[0m" : "\033[31mFAIL\033[0m").PHP_EOL;
}

foreach ($tests['long'] as $long) {
  echo "Longitude:\t$long\t\t".((validateLongitude($long)) ? "\033[32mMATCH\033[0m" : "\033[31mFAIL\033[0m").PHP_EOL;
}

foreach ($tests['lat_long'] as $lat_long) {
  $geo = explode(",", $lat_long);
  echo "Lat,Long:\t$lat_long\t".((validateLatLong($geo[0],$geo[1])) ? "\033[32mMATCH\033[0m" : "\033[31mFAIL\033[0m").PHP_EOL;
}

Hi,

Nice piece of code. The test case for Lat,Long value of '49,123' fails. Why not make integer Lat,Long pair values valid as well as you do for the individual regex?

Cheers,
C-

I updated the LatLong regex so it works when integers are provided:
return preg_match('/^[-]?((([0-8]?[0-9])(\.(\d+))?)|(90(\.0+)?)),[-]?((((1[0-7][0-9])|([0-9]?[0-9]))(\.(\d+))?)|180(\.0+)?)$/', $lat.','.$long);

Cheers,
C-

Thank you @serialc for correcting the code, I noticed the issue as well.

Suggest changing float length from {1,6} to {1,20} - ran into this problem recently while working with GPS receivers, who go into ridiculous accuracy.

Because google is giving me much more decimals I needed to update the regex

For example:
'latLng' => [
'lat' => 52.52000659999999,
'lng' => 13.404953999999975
],

would not work. So I changed it like:

^(+|-)?(?:90(?:(?:.0{1,14})?)|(?:[0-9]|[1-8][0-9])(?:(?:.[0-9]{1,14})?))$

I'm searching for google formatted locations as well. Thanks for mentioning that @pmochine.

here's a smaller implementation:

function validateLatitude(float $latitude): bool
{
    return $latitude <= 90 && $latitude >= -90;
}

function validateLongitude(float $longitude): bool
{
    return $longitude <= 180 && $longitude > -180;
}

heres very shorted version :)
function validateCoordinate($latitude, $longitude) { return is_numeric($latitude) && is_numeric($longitude); }

@kuz1toro that allows invalid coordinates such as 104,207

  /**
 * Validates a given coordinate
 *
 * @param float|int|string $lat Latitude
 * @param float|int|string $long Longitude
 * @return bool `true` if the coordinate is valid, `false` if not
 */
function is_coordinate($lat, $long) {

    $lat_pattern  = '/\A[+-]?(?:90(?:\.0{1,18})?|\d(?(?<=9)|\d?)\.\d{1,18})\z/x';
    $long_pattern = '/\A[+-]?(?:180(?:\.0{1,18})?|(?:1[0-7]\d|\d{1,2})\.\d{1,18})\z/x';

    if (preg_match($lat_pattern, $lat) && preg_match($long_pattern, $long)) {
        return true;
    } else {
        return false;
    }
}


/* These are two points in Turkey */
$point1 = array('lat' => 41.008610, 'long' => 28.971111); // Istanbul
$point2 = array('lat' => 39.925018, 'long' => 32.836956); // Anitkabir

echo '<br>';

if(!is_coordinate($point1['lat'], $point1['long'])){
    echo 'Invalid coordinate.';
} else {
    echo 'The current coordinate.';
}

echo '<br>';

if(!is_coordinate($point2['lat'], $point2['long'])){
    echo 'Invalid coordinate.';
} else {
    echo 'The current coordinate.';
}

---

1. https://github.com/aliyilmaz/Mind/blob/master/src/Mind.php#L1449
2. https://github.com/aliyilmaz/Mind/blob/master/tests/is_coordinate.php
3. https://github.com/aliyilmaz/Mind/blob/master/tests/validate.php

I don't think this we work for wgs84 projection? like 384943.343,344343.004 if yes please suggest anyone perfect. thanks

I use this regex and it works correct:

latitude:

'regex:/^[-]?(([0-8]?[0-9])\.(\d+))|(90(\.0+)?)$/'

longitude:

'regex:/^[-]?((((1[0-7][0-9])|([0-9]?[0-9]))\.(\d+))|180(\.0+)?)$/'

Northings and eastings from Nigeria can use this 'regex:/^\d{1,6}(.\d{1,3})?$/'

I use this regex and it works correct:

latitude:

'regex:/^[-]?(([0-8]?[0-9])\.(\d+))|(90(\.0+)?)$/'

longitude:

'regex:/^[-]?((((1[0-7][0-9])|([0-9]?[0-9]))\.(\d+))|180(\.0+)?)$/'

i will try this on lat an long thanks

echo preg_match('/^[-]?(([0-8]?[0-9]).(\d+))|(90(.0+)?),[-]?((((1[0-7][0-9])|([0-9]?[0-9])).(\d+))|180(.0+)?)$/', '41.883551-82.702518');

I removed the comma and it still returns 1, is there a way to have it so it fails if no comma?

echo preg_match('/^[-]?(([0-8]?[0-9]).(\d+))|(90(.0+)?),[-]?((((1[0-7][0-9])|([0-9]?[0-9])).(\d+))|180(.0+)?)$/', '41.883551-82.702518');

I removed the comma and it still returns 1, is there a way to have it so it fails if no comma?

Maybe you should try and elaborate on what the problem is .

but it is not valid in the case of "--",
I used this regex but it accepted"--78798989898" case which is wrong, Can anyone suggest me something?

but it is not valid in the case of "--", I used this regex but it accepted"--78798989898" case which is wrong, Can anyone suggest me something?

can you tell me the format of the result you want to obtain?