在PHP中应用欧几里得距离公式

Question

这里是我的欧几里德方程的furmula实现。

$i = 0; 
    $min = 0; 

    while ($row = @mysqli_fetch_array($result)) 

    { 

     $pcount = $row['pcount']; 

     $ncount = $row['ncount']; 

     echo "pcount is $pcount<br/>"; 

     echo "ncount is $ncount<br/></br>"; 
     $a[$i] = $pcoutn ; 
     $b[$i] = $pcoutn ; 
     while ($row = @mysqli_fetch_array($result)) 

     { 

      $a[$j] = $row['pcount']; 
      $b[$j] = $row['ncount']; 
      $diff = sqrt(($a[$i] - $a[$j])^2 + ($b[$i] - $b[$j])^2) 
      $j= $j + 1; 
      echo "$diff <br>"; 
     }    
     $i = $i + 1;   


    } 

什么是语法错误？

错误是：Parse error: syntax error, unexpected '$j' (T_VARIABLE)

Answer 1

你就行跳过;

$diff = sqrt(($a[$i] - $a[$j])^2 + ($b[$i] - $b[$j])^2) 

使用

$diff = sqrt(($a[$i] - $a[$j])^2 + ($b[$i] - $b[$j])^2);