<?php
  $testArray=array("key1"=>"Value1","key2"=>"Value2","key3"=>"Value3");
  print_r(array_change_key_case($testArray,CASE_UPPER));
  //Array ( [KEY1] => Value1 [KEY2] => Value2 [KEY3] => Value3 )
?>

<?php
 $testArray = array(2.4, 2.6, 3.5);
 print_r(array_map('ceil', $testArray));
 // Array ( [0] => 3 [1] => 3 [2] => 4 )

 $testArray = array(2.4, 2.6, 3.5);
 print_r(array_map('floor', $testArray));
 // Array ( [0] => 2 [1] => 2 [2] => 3 )
?>