PHP: Suma diferentes valores de matriz multidimensional - php, matrices, matriz multidimensional, foreach, suma

Necesito sumar los totales de "in" y "ou", [a] a [t] La matriz.

Array
(
[1] => Array
(
[in] => Array
(
[a] => 3
[b] => 0
[c] => 0
[d] => 0
[e] => 0
[f] => 0
[o] => 0
[t] => 3
)

[ou] => Array
(
[a] => 0
[b] => 0
[c] => 1
[d] => 0
[e] => 0
[f] => 0
[o] => 0
[t] => 1
)
)
[2] => Array
(
[in] => Array
(
[a] => 0
[b] => 0
[c] => 0
[d] => 0
[e] => 0
[f] => 0
[o] => 0
[t] => 0
)

[ou] => Array
(
[a] => 0
[b] => 0
[c] => 0
[d] => 1
[e] => 2
[f] => 0
[o] => 0
[t] => 3
)
)
)

Lo siguiente es cómo estoy calculando los totales "en" + "ou". Sin embargo, parece que estoy atascado en una rutina cuando se trata de los totales individuales de "in" a, b, c, d, e, f, t y "ou" a, b, c, d, e, f, t

//get day total
foreach($arr as $array){
foreach($array as $inou){
foreach(array_keys($inou) as $value){
if(isset($total[$value])){
$total[$value] += $inou[$value];
}else{
$total[$value] = $inou[$value];
}
}
}
}

La salida debe verse algo como

in(
[a] => 3
[b] => 0
[c] => 0
...
[t] => 3
)
ou(
[a] => 0
[b] => 0
[c] => 1
[d] => 1
[e] => 2
[f] => 0
[t] => 4
)

Respuestas

Esto debería ayudarte a comenzar:

        $sumIN = 0;
$sumOU = 0;
foreach($arr as $innerArr)
{
$sumIN += array_sum($innerArr["in"]);
$sumOU += array_sum($innerArr["ou"]);
}