Compare array values to variables

Question

I have an array that I fetched using While Loop and I want to compare to two php variables. The two variables are from the jQuery range slider. The slider variables are:

$startSlider;
$endSlider;

And compare them to an array fetched using mysql_fetch_array using the While Loop:

$query2 = "SELECT startShift,endShift from seats where seatid=".$row['seatid'];
$result2 = mysql_query($query2);
    while ($row2 = mysql_fetch_array($result2)){
        echo $row2['startShift']."-".$row2['endShift'];
        echo "<br>";
    }

The result of that would be:

Array of start shifts and end shifts for each block.

As you can see in block 11 there are 2 sets of values/array because I have two rows that have the same seatid but different startShift and endShift:

How do I compare them to the two range slider values. For example, compare the 720 and 360 to $startSlider and the 1080 and 600 to $endSlider.

What I want is:

IF $starSlider to $endSlider is not equal or overlaps $startShift to $endShift{
$blockColor = yellow;}

I've been trying to come up with an algorithm but Im just a beginner in PHP. I hope my question is clear. Any kind of help is appreciated. Thank you in advance.

Example: $startSlider=300; $endSlider=450;

The range 300-450 overlaps the range 360-600 in block 11. If either of the 360-600 and 720-1080 range is overlapped. It would return false.

What does it mean to `overlap`? Can you explain it with numbers? Create an example of `overlap` and see where does that get you. It is not really hard. — dkasipovic, Feb 28 '14 at 10:10
On a pure technical level, the comparison is `$row2['startShift'] < $startSlider`. Substitute `<` for whatever comparison you want to do exactly. Beyond that, it's rather unclear what exactly you want to compare in what way. — deceze, Feb 28 '14 at 10:15
I added an example in numbers in my post in the lowest part. I hope it makes sense. — rez, Feb 28 '14 at 10:16
Perhaps this will help: http://stackoverflow.com/a/143568/476 — deceze, Feb 28 '14 at 10:17
Note that the mysql extension is outdated and deprecated. Use mysqli or PDO instead; each has important advantages over the old extension, not the least of which is support for prepared statements. As for your question, if you can answer Kasipovic's questions, you'll be able to answer your own, so give them a shot. — outis, Mar 01 '14 at 05:57

score 0 · Answer 1 · answered Feb 28 '14 at 10:19

0

Do not overwrite the index of array create new index and you can compare the value

answered Feb 28 '14 at 10:19

D-2020365

82
1
11

score 0 · Answer 2 · answered Feb 28 '14 at 10:19

I don't really understand what you want to achieve (Especially, when you say overlap, what do you mean).

But if this will help.. Cheers...

$query2 = "SELECT startShift,endShift from seats where seatid=".$row['seatid'];
$result2 = mysql_query($query2);
    while ($row2 = mysql_fetch_array($result2)){
        if($row2['startShift'] == $startSlider && $row2['endShift'] == $endSlider){

                Do your echo here and include html to define the colour.

        }

    }

Ryan Vincent · Accepted Answer · 2014-03-04T09:42:50.123

I created some code to try and help with your overlap test...

first i created a procedure to check for overlapping ranges. here is the code...

/*
 * A range is declared as an associated array as follows
 * array(
 *   'start' => <integer value>
 *   'end'   => integer  value>
 *  )
 *
 *  where 'start' is always less than or equal to 'end'.
 *
 * e.g. array('start' => 350, 'end' => 450)
 *
 */

/*
 * To show the logic more clearly we will create a function that detects whether
 * ranges overlap or not as follows:
 *
 * It will accept two ranges:
 *   1) a 'target' range that is being tested against.
 *   2) a 'source' range that may overlap the 'target' range
 *
 * The function will return a single integer as follows:
 *
 * result
 * -1 ==> the 'source' range is completely outside the 'target' range
 *  0 ==> the 'source' range overlaps the 'target' range
 * +1 ==> the 'source' range is completely inside the target range
 *
 * The function is not the most efficient but hopefully is clear to understand.
 */

function check_range_overlap(array $targetRange, array $sourceRange)
{
  // is the source range completely outside?
  $isOutside =    $sourceRange['end']   < $targetRange['start']
               || $sourceRange['start'] > $targetRange['end'];


  // is the source range completely inside?
  $isInside =     $sourceRange['start'] >= $targetRange['start']
               && $sourceRange['end']   <= $targetRange['end'];


  // now see which of the above are true. if none are then the source overlaps overlaps.
  // i am not interested in how much the range overlaps

  if ($isOutside) {
    $overlapResult = -1; // completely outside
  }
  elseif ($isInside)
    $overlapResult = 1; // completely inside

  else
    $overlapResult = 0; // overlaps somehow - i do note care how much or where


  return $overlapResult;
}

/*
 * Test it...
 */

/* */
$target = array('start' => 100, 'end' => 200);

// completely outside less than
$source = array( 'start' => 10, 'end' => 90);
echo '<br/>Outside test: less than: ', check_range_overlap($target, $source) === -1 ? 'true' : 'false';

// completely outside greater than
$source = array( 'start' => 300, 'end' => 400);
echo '<br/>Outside test: greater than: ', check_range_overlap($target, $source) === -1 ? 'true' : 'false';

// completely inside - smaller range
$source = array( 'start' => 110, 'end' => 190);
echo '<br/>Inside test: smaller range: ', check_range_overlap($target, $source) === 1 ? 'true' : 'false';

// completely inside - equal range
$source = array( 'start' => 100, 'end' => 200);
echo '<br/>Inside test: equal range: ', check_range_overlap($target, $source) === 1 ? 'true' : 'false';

// overlap - start only
$source = array( 'start' => 50, 'end' => 120);
echo '<br/>Inside test: equal range: ', check_range_overlap($target, $source) === 0 ? 'true' : 'false';

// overlap - end only
$source = array( 'start' => 150, 'end' => 220);
echo '<br/>Inside test: equal range: ', check_range_overlap($target, $source) === 0 ? 'true' : 'false';

// overlap - start and end .i.e larger than target.
$source = array( 'start' => 90, 'end' => 220);
echo '<br/>Inside test: equal range: ', check_range_overlap($target, $source) === 0 ? 'true' : 'false';
/* */

/*
 *  ---------------------------  Function definition and test end ------------------
 */

Next, i created a test database with the following structure and data in it:

/*
  * Table seat details:
  *
  * id  seatid  startShift  endShift
------  ------  ----------  ----------
     1      11         720        1080
     2      11         360         600
     3       9         720        1080
     4       8         360         600
     5      90         100         200
     6      91         200         300
     7      92         300         400
  */

Then i executed one seatid to ensure it did something sensible:

/*
 * now the mysql database stuff...
 */

$db = new mysqli('localhost', 'test', 'test', 'testmysql');

$seatIdQuery = $db->prepare('SELECT seatid, startShift,endShift from seats where seatid = ?');
if ($db->errno) {
  echo '<br/>prepare error: ', $db->errno, ' : ', $db->error, '<br/>';
}

$currentSeatId = 0; // current seat id we will use

// bind the currentSeatId to the 'seatIdQuery'
$seatIdQuery->bind_param('i', $currentSeatId);


/*
  * This is the start of the code to process one source range against one seatid and display the results
  */
 $currentSeatId = 8; // current seat id

 $allOk = $seatIdQuery->execute(); // execute the prepared query with the seatId of 8

 $results = $seatIdQuery->get_result(); // get the query result set

$sourceRange = array('start' => 350, 'end' => 450); // source range -- from slider...


while ($row =  $results->fetch_assoc()) { // for each seatid row returned

  // check against the 'seatid' range
  $targetRange = array('start' => $row['startShift'], 'end' => $row['endShift']);

  $overlapCheck = check_range_overlap($targetRange, $sourceRange);

  // prepare range overlap message
  if ($overlapCheck < 0) {
     $overlapText = 'source range is Outside.';
  }
  elseif ($overlapCheck >= 1) {
     $overlapText = 'source range is Inside';
  }
 else {
     $overlapText = 'source range OVERLAPS';
  }

  // show the result
  echo '<br/>seatid: ', $row['seatid'],
             ' seatRange: ', $row['startShift'], ' - ', $row['endShift'],
             ' result: ',  $overlapText;
 }
 /*
  * This is the end of code to process one source range against one seatid and display the results
  */

Here is the output from the above seatid of 8...

seatid: 8 seatRange: 360 - 600 result: source range OVERLAPS

Compare array values to variables

3 Answers3