print_r(3) [php man page]

PRINT_R(3)								 1								PRINT_R(3)

print_r - Prints human-readable information about a variable

SYNOPSIS

       mixed print_r (mixed  $expression, [bool  $return = false])

DESCRIPTION

       print_r(3) displays information about a variable in a way that's readable by humans.

       print_r(3),  var_dump(3) and var_export(3) will also show protected and private properties of objects with PHP 5. Static class members will
       not be shown.

PARAMETERS

	      o $expression
		- The expression to be printed.

	      o $return
		- If you would like to capture the output of print_r(3), use the $return parameter. When this parameter is set to TRUE, print_r(3)
		will return the information rather than print it.

RETURN VALUES

	If  given a string, integer or float, the value itself will be printed. If given an array, values will be presented in a format that shows
       keys and elements. Similar notation is used for objects.

	When the $return parameter is TRUE, this function will return a string. Otherwise, the return value is TRUE.

NOTES

       Note

	      When the $return parameter is used, this function uses internal output buffering so it cannot be used inside an ob_start(3) callback
	      function.

EXAMPLES

       Example #1

	      print_r(3) example

	      <pre>
	      <?php
	      $a = array ('a' => 'apple', 'b' => 'banana', 'c' => array ('x', 'y', 'z'));
	      print_r ($a);
	      ?>
	      </pre>

	      The above example will output:

	      <pre>
	      Array
	      (
		  [a] => apple
		  [b] => banana
		  [c] => Array
		      (
			  [0] => x
			  [1] => y
			  [2] => z
		      )
	      )
	      </pre>

       Example #2

	      $return parameter example

	      <?php
	      $b = array ('m' => 'monkey', 'foo' => 'bar', 'x' => array ('x', 'y', 'z'));
	      $results = print_r($b, true); // $results now contains output from print_r
	      ?>

SEE ALSO

       ob_start(3), var_dump(3), var_export(3).

PHP Documentation Group 														PRINT_R(3)

ARRAY_FILTER(3) 							 1							   ARRAY_FILTER(3)

array_filter - Filters elements of an array using a callback function

SYNOPSIS

       array array_filter (array  $array, [callable  $callback], [int  $flag])

DESCRIPTION

	Iterates  over	each value in the $array passing them to the $callback function. If the $callback function returns true, the current value
       from $array is returned into the result array. Array keys are preserved.

PARAMETERS

	      o $array
		- The array to iterate over

	      o $callback
		- The callback function to use	If no $callback is supplied, all entries of $array equal to FALSE (see converting to boolean) will
		be removed.

	      o $flag
		- Flag determining what arguments are sent to $callback:

		     o ARRAY_FILTER_USE_KEY - pass key as the only argument to $callback instead of the value

		     o ARRAY_FILTER_USE_BOTH - pass both value and key as arguments to $callback instead of the value

RETURN VALUES

	Returns the filtered array.

CHANGELOG

       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       | 5.6.0	|						    |
       |	|						    |
       |	|  Added  optional  $flag  parameter  and constants |
       |	| ARRAY_FILTER_USE_KEY and ARRAY_FILTER_USE_BOTH    |
       |	|						    |
       +--------+---------------------------------------------------+
EXAMPLES

       Example #1

	      array_filter(3) example

	      <?php
	      function odd($var)
	      {
		  // returns whether the input integer is odd
		  return($var & 1);
	      }

	      function even($var)
	      {
		  // returns whether the input integer is even
		  return(!($var & 1));
	      }

	      $array1 = array("a"=>1, "b"=>2, "c"=>3, "d"=>4, "e"=>5);
	      $array2 = array(6, 7, 8, 9, 10, 11, 12);

	      echo "Odd :
";
	      print_r(array_filter($array1, "odd"));
	      echo "Even:
";
	      print_r(array_filter($array2, "even"));
	      ?>

	      The above example will output:

	      Odd :
	      Array
	      (
		  [a] => 1
		  [c] => 3
		  [e] => 5
	      )
	      Even:
	      Array
	      (
		  [0] => 6
		  [2] => 8
		  [4] => 10
		  [6] => 12
	      )

       Example #2

	      array_filter(3) without $callback

	      <?php

	      $entry = array(
			   0 => 'foo',
			   1 => false,
			   2 => -1,
			   3 => null,
			   4 => ''
			);

	      print_r(array_filter($entry));
	      ?>

	      The above example will output:

	      Array
	      (
		  [0] => foo
		  [2] => -1
	      )

       Example #3

	      array_filter(3) with $flag

	      <?php

	      $arr = ['a' => 1, 'b' => 2, 'c' => 3, 'd' => 4];

	      var_dump(array_filter($arr, function($k) {
		  return $k == 'b';
	      }, ARRAY_FILTER_USE_KEY));

	      var_dump(array_filter($arr, function($v, $k) {
		  return $k == 'b' || $v == 4;
	      }, ARRAY_FILTER_USE_BOTH));
	      ?>

	      The above example will output:

	      array(1) {
		["b"]=>
		int(2)
	      }
	      array(2) {
		["b"]=>
		int(2)
		["d"]=>
		int(4)
	      }

NOTES

       Caution

	       If the array is changed from the callback function (e.g. element added, deleted or unset) the behavior of this  function  is  unde-
	      fined.

SEE ALSO

       array_map(3), array_reduce(3), array_walk(3).

PHP Documentation Group 													   ARRAY_FILTER(3)