PHP:如何查找最常用的数组键？

Question

假设我有一个简单的1D阵列,有10-20个条目.有些会重复,我怎样才能找出最常使用的条目？喜欢..

$code = Array("test" , "cat" , "test" , "this", "that", "then");

我如何将"test"显示为最常用的条目？

Answer 1

$code = Array("test" , "cat" , "test" , "this", "that", "then");

function array_most_common($input) { 
  $counted = array_count_values($input); 
  arsort($counted); 
  return(key($counted));     
}

echo '<pre>';
print_r(array_most_common($code));

Answer 2

您可以使用array_count_values计算每个值的出现次数.

$code = array("test" , "cat" , "cat", "test" , "this", "that", "then");
$counts = array_count_values($code);
var_dump($counts);
/*
array(5) {
  ["test"]=>
  int(2)
  ["cat"]=>
  int(2)
  ["this"]=>
  int(1)
  ["that"]=>
  int(1)
  ["then"]=>
  int(1)
}
*/

要获得最常出现的值,可以在数组上调用max,然后使用array_search访问(第一个)值.

$code = array("test" , "cat" , "cat", "test" , "this", "that", "then");
$counts = array_count_values($code);
$max = max($counts);
$top = array_search($max, $counts);
var_dump($max, $top);
/*
int(2)
string(4) "test"
*/

如果您希望满足多个最常用的值,那么以下内容将起作用:

$code = array("test" , "cat" , "cat", "test" , "this", "that", "then");
$counts = array_count_values($code);
$max = max($counts);
$top = array_keys($counts, $max);
var_dump($max, $top);
/*
int(2)
array(2) {
  [0]=>
  string(4) "test"
  [1]=>
  string(3) "cat"
}
*/