How to iterate multi dimensional array and calculate sum for each row in php?

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i have this array which i retrieved data from my database and put it in an array :

$query = "select * from caseunder"; 
$result=mysql_query($query) or die('Error, insert query failed'); 
$array[] = array();
$numrows=mysql_num_rows($result); 
WHILE ($i < $numrows){ 
    $allergies =mysql_result($result, $i, "allergies");  
    $vege = mysql_result($result,$i, "vege");  
    $age = mysql_result($result, $i, "age");  
    $bmi =mysql_result($result, $i, "bmi"); 
    $solution = mysql_result($result,$i, "solution"); 
    $bmi2 = $_POST['weight'] / (($_POST['height']/100)*($_POST['height']/100));
    if($_POST['age']>18 && $_POST['age']<35)
        $age2 = 'young ';
    if($_POST['age']>40 && $_POST['age']<50)
        $age2 = 'middle age ';
    if($_POST['age']>60)
        $age2 = 'old men ';
    $array[] = array('age'=>$age2,'allergies'=>$allergies,'vege'=>$vege,'bmi'=>$bmi2,'solution'=>$solution);

    i++
}

Then, i want to compare each element in that array with input i entered and calculate sum for each row of array :

foreach($array as $cases) {

    if($cases['allergies'] == $_POST['allergies']){
        $count = 1;
    }

    if($cases['vege'] == $_POST['vege']){
        $count1 = 1;
    }

    if($cases['bmi'] == $bmi2)
        $count2 = 1;

    if($cases['age'] == $age2)
        $count3 = 1;

    $sum = $count + $count1 + $count2 + $count3;
    echo $sum;
}

Lets say i have entered age,bmi, allergies and vege which is all are the same like first row of database, the the total sum that should be output is 4 because 4 same comparison of data. In this case that i try, every row of database should have different total sum because its not all the same.But i did not get the output that i want, this is the example of the wrong output:

0
4
4
4
4
4
4
4
4

(assuming i have 8 rows of database in my phpmyadmin) The first row of database after compared manually the sum is 4 but it seems like when it continue looping the next row take the same amount as prev row.

3

There are 3 answers

0
Don't Panic On BEST ANSWER

When you do this loop:

foreach($array as $cases) {

    if($cases['allergies'] == $_POST['allergies']){
        $count = 1;
    }
    if($cases['vege'] == $_POST['vege']){
        $count1 = 1;
    }
    if($cases['bmi'] == $bmi2)
        $count2 = 1;
    if($cases['age'] == $age2)
        $count3 = 1;
    $sum = $count + $count1 + $count2 + $count3;
    echo $sum;
}

You are not resetting the $count, $count1, etc. variables between iterations. That is why

when it continue looping the next row take the same amount as prev row.

I would say you probably don't even need these separate variables unless you are using them for something else that isn't included in the question. You can just initialize sum to zero for each repetition, then increment it directly if the conditions match.

foreach($array as $cases) {
    $sum = 0;   
    if($cases['allergies'] == $_POST['allergies']){
        $sum++;
    }
    if($cases['vege'] == $_POST['vege']){
        $sum++;
    }
    if($cases['bmi'] == $bmi2) {
        $sum++;
    }
    if($cases['age'] == $age2) {
        $sum++;
    }
    echo $sum;
}

Incidentally, it looks like the way you are setting bmi and age in the first loop will make those values always match. I'm not sure if that's what you intended, but it seems kind of unlikely.

0
Leonardo Zimmermann On
// Start variable sum    
    $sum = 0:
// For each $_POST[] in array
    foreach($_POST as $key => $value){
// If Key in $_POST exists add sum
       if(array_key_exists($key,$array)){
         ++$sum;
       }
    }
echo $sum;
1
GolezTrol On

This is wrong:

foreach($array as $array)

You take the multi-dimensional array, which goes by the name $array, and iterate over each item in it, which is also assigned to $array. This is asking for weird behavior. Use a different variable. Array variables don't have to be named $array.