Question

我在这里没有想法。我有：

d1 = {1:30, 2:20, 3:30, 5:80}
d2 = {1:40, 2:50, 3:60, 4:70, 6:90}

我想创建：

d3 = {4:70, 5:80, 6:90}

我意识到这是多么微不足道，因此我感到沮丧。如果您有任何想法，请分享。

Answer 1

对称差异^找到唯一键。然后它是一个简单的词典理解：

>>> {k: d1.get(k, d2.get(k)) for k in (set(d1) ^ set(d2))}
{4: 70, 5: 80, 6: 90}

上面的方法是交叉比较代码。如果你不需要处理Python 2，它看起来会更好一些：

>>> from collections import ChainMap
>>> d12 = ChainMap(d1, d2)
>>> {k: d12[k] for k in d1.keys() ^ d2.keys()}
{4: 70, 5: 80, 6: 90}

注意：键＆＃34;查看＆＃34;这里的对象也可以在方法d.viewkeys()下的Python 2中获得。

Answer 2

<?php $mysql_hostname = "localhost"; 
$mysql_user = "root";
$mysql_password = "";
$mysql_database = "test";
$prefix = "";
$bd = mysql_connect($mysql_hostname, $mysql_user, $mysql_password) or die("Could not connect database");
mysql_query("SET NAMES UTF8");
mysql_select_db($mysql_database, $bd) or die("Could not select database");
require_once './Classes/PHPExcel.php';
$objPHPExcel = new PHPExcel();

$query = "SELECT * FROM testing";

$result = mysql_query($query) or die(mysql_error());

//$objPHPExcel = new PHPExcel();

 $rowCount = 2;

 while($row = mysql_fetch_array($result)){
  $objPHPExcel->getActiveSheet()->SetCellValue('A1','ID');
  $objPHPExcel->getActiveSheet()->SetCellValue('A'.$rowCount, $row['id']);
  $objPHPExcel->getActiveSheet()->SetCellValue('B1','name');
  $objPHPExcel->getActiveSheet()->SetCellValue('B'.$rowCount, $row['name']);
  $objPHPExcel->getActiveSheet()->SetCellValue('C1','file_path');
  $objPHPExcel->getActiveSheet()->SetCellValue('C'.$rowCount, $row['file_path']);
  $objPHPExcel->getActiveSheet()->SetCellValue('D1','date');
  $objPHPExcel->getActiveSheet()->SetCellValue('D'.$rowCount, $row['date']);
  $objPHPExcel->getActiveSheet()->getCell('C'.$rowCount, $row['file_path'])->getHyperlink()->setUrl();
  $rowCount++;
}
ob_end_clean();
 header('Content-Type: application/vnd.openxmlformats-   officedocument.spreadsheetml.sheet');
 header('Content-Disposition: attachment;filename="Test_list.xls"');
 header('Cache-Control: max-age=0');

 $objWriter = PHPExcel_IOFactory::createWriter($objPHPExcel, 'Excel5');
 $objWriter->save('php://output');
 exit;
?>

创建一个字典（d3），其中包含两个其他词典特有的项目（d1，d2）

2 个答案: