how to search min and max values in 2D array - php

Question

am trying to find out min x and min y values in whole array , i tried with min and max function but no success so far
i have xy values of board in 2d array
$xydata = array(
array('x' => 17.0, 'y' => 2.83),
array('x' => 20.83, 'y' => 65.37 ),
array('x' => 17.85,'y' => 3.57 ),
array('x' => 17.13, 'y' => 41.33 ),
array('x' => 24.27, 'y' => 53.48 ),
array('x' => 13.1, 'y' => 16.35),
array('x' => 13.1, 'y' => 66.855 )
);
i want to find corners of board
globally i have min x/y max x/y which i got through min() and max () functions
what i want is to get min y against min x
like if through $xydata i search with min x which is 13.1 i should get min y 16.35 because the other min x 13.1 y value is 66.855 is higher .... so any idea how it could be done

Answer 1

Sample code:
$xydata = array(
array('x' => 17.0, 'y' => 2.83),
array('x' => 20.83, 'y' => 65.37 ),
array('x' => 17.85,'y' => 3.57 ),
array('x' => 17.13, 'y' => 41.33 ),
array('x' => 24.27, 'y' => 53.48 ),
array('x' => 13.1, 'y' => 66.855 ),
array('x' => 13.1, 'y' => 16.35),
);
$min = $xydata[0];
foreach ($xydata as $d) {
if ($d['x'] < $min['x'] || ($d['x'] == $min['x'] && $d['y'] < $min['y'])) {
$min = $d;
}
}
echo'<pre>',print_r($min),'</pre>'; // TODO

Answer 2

Try this, best solution is use shorting of array
$xydata = array(
array('x' => 17.0, 'y' => 2.83),
array('x' => 20.83, 'y' => 65.37 ),
array('x' => 17.85,'y' => 3.57 ),
array('x' => 17.13, 'y' => 41.33 ),
array('x' => 24.27, 'y' => 53.48 ),
array('x' => 13.1, 'y' => 16.35),
array('x' => 13.1, 'y' => 66.855 )
);
$count = 0;
foreach ($xydata as $type) {
$count++;
}
$count--;
function sortByOrder($a, $b) {
return $a['x'] - $b['x'];
}
usort($xydata, 'sortByOrder');
echo "min of x => ".$xydata [0]['x'];
echo "max of x => ".$xydata [$count]['x'];
function sortByOrdery($a, $b) {
return $a['y'] - $b['y'];
}
usort($xydata, 'sortByOrdery');
echo "min of y => ".$xydata [0]['y'];
echo "max of y => ".$xydata [$count]['y'];
DEMO

Answer 3

You can try the below functions:
function array_max($a) {
foreach ($a as $value) {
if (is_array($value)) {
$value = array_max($value);
}
if (!(isset($max))) {
$max = $value;
} else {
$max = $value > $max ? $value : $max;
}
}
return $max;
}
function array_min($a) {
foreach ($a as $value) {
if (is_array($value)) {
$value = array_min($value);
}
if (!(isset($min))) {
$min = $value;
} else {
$min = $value < $min ? $value : $min;
}
}
return $min;
}
Its work fine for me :)

Answer 4

You can use array_multisort to build a function that will give you all possible pairs of min/max:
function getXY(array $xyArray, $x = 'min', $y = 'min')
{
$xFlag = $x === 'max' ? SORT_DESC : SORT_ASC;
$yFlag = $y === 'max' ? SORT_DESC : SORT_ASC;
array_multisort(
array_column($xyArray, 'x'), $xFlag,
array_column($xyArray, 'y'), $yFlag,
$xyArray
);
return array_shift($xyArray);
}
Here is working demo.