PHP Functions

1) abs

        Return the absolute value of different numbers:
Example:

       echo abs(-4)."<br>";
       echo abs(-5.3)."<br>";
       echo abs(2)."<br>";
Output:

    4
    5.3
    2

2) arsort

       Sort an array in reverse order and maintain index association
Example: 

       $name=array('c'=>"cat",'a'=>"apple",'b'=>"ball");
       arsort($name);
       foreach ($name as $k=>$v)
      {
         echo "$k=>$v<br>";
      }
Output: 

       c=>cat
       b=>ball
       a=>apple
 
3) asort

   Sort an array and maintain index association
Example:

 $name=array('c'=>"cat",'a'=>"apple",'b'=>"ball");
asort($name);
foreach ($name as $k=>$v)
{

echo "$k=>$v<br>";
}
Output:

a=>apple
b=>ball
c=>cat

4) ceil

Round numbers up to the nearest integer

Example:
echo ceil(4.3)."<br>";
echo ceil(4.5)."<br>";
echo ceil(4.7)."<br>";


echo ceil(-4.3)."<br>";
echo ceil(-4.5)."<br>";
echo ceil(-4.7)."<br>";
Output:
 5
 5
 5
-4
-4
-4