Using Google Maps to calculate distances

MatrixOfDistances.php

<?php
header("Content-type: text/csv");
header('Content-disposition: attachment;filename="matrix.csv"');

$matrix = array( );
$titles = array();

$allPositions = array("14.597518,-90.514900",
"14.599453,-90.515419",
"14.597998,-90.512912",
"14.597389,-90.510218",
"14.599377,-90.513408",
"14.597791,-90.512088",
"14.579766,-90.495399",
"14.592630,-90.511397",
"14.609474,-90.505654",
"14.599025,-90.515651",
"14.587368,-90.513884",
"14.582139,-90.515367",
"14.576909,-90.523670",
"14.561100,-90.472302",
"14.580478,-90.492893",
"14.609463,-90.486374",
"14.597262,-90.496923",
"14.647721,-90.481787",
"14.622750,-90.552212",
"14.618189,-90.555172",
"14.620369,-90.561692",
"14.592493,-90.564815",
"14.611207,-90.597559",
"14.597130,-90.579336",
"14.602201,-90.580975",
"14.650728,-90.539538",
"14.592146,-90.493894",
"14.552698,-90.452897",
"14.635150,-90.581292",
"14.635569,-90.582361",
"14.562676,-90.464594",
"14.639643,-90.565264",
"14.624663,-90.470468",
"14.623395,-90.550826",
"14.582227,-90.546246",
"14.621855,-90.503155",
"14.643225,-90.497081",
"14.598870,-90.543208",
"14.583031,-90.566706",
"14.574058,-90.542411",
"14.289215,-90.785595");
/*$allPositions = array("14.597518,-90.514900",
"14.599453,-90.515419",
"14.597998,-90.512912",
"14.597389,-90.510218");*/

$googleMapsUrl = "https://maps.googleapis.com/maps/api/distancematrix/json?destinations=<ORIGIN>&origins=<DESTINATION>&language=es-GT&mode=driving&key=AIzaSyD6LnWTDEyiF0HRCmHaukDsMCJjnn8akDI";

$rowsToAnalyze = count($allPositions);
$lastRowAnalized = 0;
$globalRowLenght = 2;
$globalColumnLenght = 25;

while ($rowsToAnalyze > 0) {    
    $rows = array_slice($allPositions, $lastRowAnalized, $globalRowLenght);    
    $origins = implode("|", $rows);

    $columnsToAnalyze = count($allPositions);
    $lastColumnAnalized = 0;    
    while ($columnsToAnalyze > 0) {
        $columns = array_slice($allPositions, $lastColumnAnalized, $globalColumnLenght);
        $destinations = implode("|", $columns);        

        $finalUrl = str_replace("<ORIGIN>", $origins, $googleMapsUrl);
        $finalUrl = str_replace("<DESTINATION>", $destinations, $finalUrl);

        //echo $finalUrl;
        $jsonText = file_get_contents($finalUrl);
        $jsonObject = json_decode($jsonText, true);

        if (!isset($jsonObject)) {
            var_dump($jsonText);
            continue;
        }

        if ($jsonObject["status"] != "OK") {
            var_dump($jsonText);
            continue;
        }                
        for ($r = 0; $r < count($jsonObject["rows"]) ; $r++) {
            $title = $allPositions[$lastColumnAnalized + $r];            
            $row = array();
            if ($matrix[$title] != null) {
                $row = $matrix[$title];
            }

            $elements = $jsonObject["rows"][$r]["elements"];
            for ($c = 0; $c < count($elements); $c++) {
                array_push($row, $elements[$c]["distance"]["value"]); 
            }
            $matrix[$title] = $row;
        }        
        $lastColumnAnalized += $globalColumnLenght;
        $columnsToAnalyze -= $globalColumnLenght;        
    }

    $lastRowAnalized += $globalRowLenght;
    $rowsToAnalyze -= $globalRowLenght;
}

foreach ($matrix as $key => $value) {
    echo "\"".$key."\",". implode(",", $value)."\n";
}