PHP Disable round_up - php

Question

How can I disable the round up in my PHP script. If I sum up something it only displays the rounded Number.
<?php
$con=mysqli_connect("localhost","XXXX","XXXX","XXXX");
if (mysqli_connect_errno()) {
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$result = mysqli_query($con,"SELECT * FROM energrid WHERE ID = 1 ");
while($row = mysqli_fetch_array($result)) {
$wert = $row['Wert'];
}
$result = mysqli_query($con,"SELECT * FROM energrid WHERE ID = 3 ");
while($row = mysqli_fetch_array($result)) {
$wert1 = $row['Wert'];
}
mysqli_close($con);
echo "here we go.:";
echo $wert + $wert1;
?>
Ok, I guess I've found my mistake. The values are like 3,5 with a , instead of a .
How can I change that if these are values directly from the MySQL DB.?

Answer 1

1.You can use number_format function
2.optimize your code -there is no need of while loop to do this
<?php
$db = mysql_connect("localhost","username","password"); ///connect to mysql
if (!$db) {
// throw error if not connect
die("Database connection failed miserably: " . mysql_error());
}
$db_select = mysql_select_db("databasename",$db); ///select database
if (!$db_select) {
//database connection error
die("Database selection also failed miserably: " . mysql_error());
}
$sum=0;
$result = mysqli_query($db,"SELECT sum(wert) as sum FROM energrid WHERE ID in ('1','3') ");
$row = mysqli_fetch_array($result)
$sum =$row['sum'];
`enter code here`
echo number_format($sum,'number','.','');
//where number-no. of place you want to round off
?>

Answer 2

use str_replace() like this to replace the comma , in number by decimal point .
$a = "3,5";
str_replace(",",".",$a);

Answer 3

Try using a cast like this :
echo (int)$wert + (int)$wert1;
echo (float)$wert + (float)$wert1;