data = $data;
}
public function set_data($data){
$this->data = $data;
}
public function get_data($data){
return $this->data;
}
function __destruct() {
}
abstract public function calc_stats();
}
class Mean extends Operation {
public function calc_stats(){
$avg_value=0;
foreach ($this->data as $array_elem){
$avg_value+=$array_elem;
}
$avg_value/=count($this->data);
return $avg_value;
}
}
class Dispersion extends Operation {
public function calc_stats(){
$avg_value=0;
foreach ($this->data as $array_elem){
$avg_value+=$array_elem;
}
$avg_value/=count($this->data);
$disp_value=0;
foreach ($this->data as $array_elem){
$disp_value+=($array_elem-$avg_value)**2;
}
$disp_value/=count($this->data);
return $disp_value;
}
}
class Median extends Operation {
public function calc_stats(){
$sorted_arr=$this->data;
sort($sorted_arr);
if(count($sorted_arr)%2==1){
return $sorted_arr[floor(count($sorted_arr)/2)];
} else{
return ($sorted_arr[count($sorted_arr)/2]+$sorted_arr[count($sorted_arr)/2-1])/2;
}
}
}
$servername = "localhost";
$username = "root";
$password = "111111";
$database = "phplab";
// Create connection
$conn = new mysqli($servername, $username, $password, $database);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
//create options for select
$sql = "SELECT id, name FROM operations;";
$result = $conn->query($sql);
$operation_options="";
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc()) {
$operation_options.="";
}
}
//check if this is deletion
if(isset($_GET['deleteid'])){
$sql = "DELETE FROM data WHERE id=".$_GET['deleteid'].";";
$result = $conn->query($sql);
}
// check if data were added
if(isset($_POST['opdata'])){
$data_array=explode(" ", $_POST['opdata']);
$newop=NULL;
if($_POST['optype']==1){
$newop= new Mean($data_array);
} else if($_POST['optype']==2){
$newop= new Dispersion($data_array);
} else if($_POST['optype']==3){
$newop= new Median($data_array);
}
$sql = "INSERT INTO `data` VALUES (DEFAULT, '".$_POST['optype']."', '".$_POST['opdata']."', '".$newop->calc_stats()."');";
$conn->query($sql);
}
// read data from DB table
$sql = "SELECT `data`.id, `operations`.name, `data`.inputdata, `data`.outputdata FROM data INNER JOIN operations ON `operations`.id=`data`.operationid;";
$result = $conn->query($sql);
$table_body="";
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc()) {
$table_body.="