I have some code that creates a multi-dimensional array, but my result seems to be an array of arrays, which is not what I want. I want to flatten this array. How can I change this array result:
Array
(
[0] => Array
(
[0] => Array
(
[2011-11-18 00:00:00] => C
)
[1] => Array
(
[2011-11-18 00:00:00] => I
)
[2] => Array
(
[2011-11-18 00:00:00] => S
)
)
[1] => Array
(
[0] => Array
(
[2011-11-22 00:00:00] => C
)
[1] => Array
(
[2011-11-22 00:00:00] => S
)
)
)
into something that is not an "array of arrays"? Here is the code that creates the array of arrays:
$qrybilled = $this->db->query("SELECT tbltc.BILLED FROM tbltc WHERE tbltc.PN = $pn AND tbltc.Y = $taxyear AND tbltc.SCENARIO = $scenario GROUP BY BILLED");
$x = 0; $arr_billed = array();
foreach ($qrybilled->result() as $row) {
$qry = $this->db->query("SELECT tbltc.BILLED, tbltc.TC, tbltc.CAT FROM tbltc WHERE tbltc.PN = $pn AND tbltc.Y = $taxyear AND tbltc.SCENARIO = $scenario AND tbltc.BILLED = '".$row->BILLED."' GROUP BY TC");
$tmp = array();
foreach ($qry->result() as $row) {
$tmp[] = array( $row->BILLED => $row->TC);
}
$arr_billed[] = $tmp;
}
$data['billed'] = $arr_billed;
If you can suggest a better way to build the array so that it is not an "array of arrays", that would be great. Thanks for your help.
The answer from NickB worked perfectly for me and produced the following output, which is what I was looking for:
Array
(
[2011-11-18 00:00:00] => Array
(
[0] => C
[1] => I
[2] => S
)
[2011-11-22 00:00:00] => Array
(
[0] => C
[1] => S
)
)
You can loop through all of the entries in the array to create a new array.
$result = array();
foreach( $array as $inner_array)
{
foreach( $inner_array as $entry)
{
foreach( $entry as $key => $value)
{
$result[ $key ][] = $value;
}
}
}
Output:
array(2) {
["2011-11-18 00:00:00"]=>
array(3) {
[0]=>
string(1) "C"
[1]=>
string(1) "I"
[2]=>
string(1) "S"
}
["2011-11-22 00:00:00"]=>
array(2) {
[0]=>
string(1) "C"
[1]=>
string(1) "S"
}
}
While you use the same key more than one in the same array, you could return a simpler (but still nested) structure (a list of pairs -- as some languages would call it).
Assuming your data is called $data:
$compactData = array();
array_walk_recursive($data, function($value, $key) use (&$compactData) {
$compactData[] = array($key, $value);
});
print_r($compactData);
Prints:
Array
(
[0] => Array
(
[0] => 2011-11-18 00:00:00
[1] => C
)
[1] => Array
(
[0] => 2011-11-18 00:00:00
[1] => I
)
[2] => Array
(
[0] => 2011-11-18 00:00:00
[1] => S
)
[3] => Array
(
[0] => 2011-11-22 00:00:00
[1] => C
)
[4] => Array
(
[0] => 2011-11-22 00:00:00
[1] => S
)
)