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這裏是我的歐幾里德方程的furmula實現。在PHP中應用歐幾里得距離公式
$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 = $i + 1;
}
什麼是語法錯誤?
錯誤是:Parse error: syntax error, unexpected '$j' (T_VARIABLE)
你缺少後'$ DIFF =開方分號(($ A [$ I ] - $ a [$ j])^ 2 +($ b [$ i] - $ b [$ j])^ 2)' –
'^'是['xor'](http://www.php .net/manual/language.operators.bitwise.php)運算符。所以即使沒有語法錯誤,你的endresult也會出錯。改用['pow'](http://php.net/manual/function.pow.php)。 – Yoshi