PHP Arrays... How do they work?

Alright… in my pursuit to convert my current site from Coldfusion to PHP, I ran into a problem with making CFC functions into PHP functions. Pretty much what I’m doing is recreating a proximity search. I think I’ve almost got it but I don’t know how PHP handles arrays and how to call to them. Here is the code I have…

//constant variables
//pi divided by 180
$piDivRad = 0.0174;
//number of miles per degree of latitude
$latitudeMiles = 69.1;
//radius of the earth in miles
$earthRadius = 3956;

//makes an array with coordinates reset to zero
function newCoordinates() {
	$newCoor = array();
	$newCoor['latitude'] = 0;
	$newCoor['longitude'] = 0;
	$newCoor['rlatitude'] = 0;
	$newCoor['rlongitude'] = 0;

//finds the coordinates from the list in the database by using the zipcode given
function zipCoordinates($zip) {
	$zipCoor = newCorordinates();
	$query = "SELECT latitude, longitude, rlatitude, rlongitude FROM zipcodes WHERE zip = '$zip'";
	$result = mysql_query($query);
	if ($zipcode = mysql_fetch_array($result)) {
		$zipCoor['latitude'] = $zipcode['latitude'];
		$zipCoor['longitude'] = $zipcode['longitude'];
		$zipCoor['rlatitude'] = $zipcode['rlatitude'];
		$zipCoor['rlongitude'] = $zipcode['rlongitude'];
	//return the coordinates for the lat and long
	return $zipCoor;

function squareSearch($radius, $zip) {
	$radius = $radius; //maybe not needed?
	$zip = $zip; //maybe not needed?
	$zipCoor = zipCoordinates($zip);
	$formula = $earthRadius * (ACOS((SIN($zipCoor['latitude']/57.2958) * SIN(latitude/57.2958)) + (COS($zipCoor['latitude']/57.2958) * COS(latitude/57.2958) * COS(longitude/57.2958 - $zipCoor['longitude']/57.2958))))
	$query = "SELECT zip, latitude, longitude, '$formula' FROM zipcodes WHERE '$formula' <= '$radius'";
	$result = mysql_query($query);
        //return the results
	return $result;

Alright… for the function zipCoordinates I have a variable ($zipCoor) calling the function newCorordinates().

$zipCoor = newCorordinates();

Because the function creates an array, will the variable $zipCoor become an array?
$zipCoor = [0, 0, 0, 0]?

Also is my if statement correct in zipCoordinates()?

Last, since squareSearch() will return multiple results will I need to make a while statement? or is the return $result at the end of the function sufficient?