PHP How to get a boolean average of an array - php

Question

EDIT2: This goes to the top for a reason. This question is asked wrong, but I won´t change the title, since maybe other people are caught in this misstake. I am NOT looking for an "average" - I merely want to exit with the first "false" in an array.
My though to this questions were quite twisted - therefore I asked the wrong question.
Anyway: As stated, I won´t change the question itself.
What I want to do is basically calculate something like a boolean average of an array. I know about booleans and that they are not meant to be something with an average, but please read on to see what I am doing.
My array looks like this:
$array = array(
true,
false,
true,
true
);
I now want to get an AND-operation done on this array to see, if everything in there is true or if a subfunction returned false. This is basically a list of results from different subfunctions.
This specific example then should return false, because $array[1] is false.
EDIT:
What I am looking for is a builtin PHP-function which seems not to exists. A custom implementation has the advantage to exit the iteration over this array in comparison to in_array() which might not do this.
Can you help me out, stackoverflow?

Answer 1

Try in_array:
$array = array(
true,
false,
true,
true
);
echo in_array(false, $array);
If one of the elements is false, it will return false otherwise it returns true.
Update: in_array, returns out of the loop as soon as the searched value is matched. The worst case I suppose is when you have a single false at the end of the searched array. The linked source are for PHP 5.3.
As far as strict checking is concerned, you can do so passing in the third parameter to in_array:
echo in_array(false, $array, true);

Answer 2

Come on, it would appear you didn't even try:
function checkArray(array $in)
{
foreach ($in as $bool)
{
if (!$bool)//replace with type&value checking if that's what you're after
return false;
}
return true;
}
var_dump(checkArray(array(true, false, true, true)));//false
var_dump(checkArray(array(true, true)));//true
There are, of course, a bunch of alternative ways to do what you want/need, depending on what the actual data will look like. If it's all booleans:
if (array_sum($array) != count($array))
{//true == 1, array_sum(array(true, true)) == count(array(true, true)) == 2
echo 'array contains false, or non-boolean values, like 123';
}
//for a real average:
$avg = round(array_sum($array)/count($array));
The latter will yield 1 if 50%>= of the values in the array are true, and 0 otherwise. It's then a simple matter of casting that value to a boolean to get the "average bool value":
$avg = (bool) round(
array_sum($array)/count($array)
);
or, for example:
$valsAsKey = array_flip(
array_map(
'intval',//make ints
$array
)
);
if (isset($valsAsKey[0]))
{//(int) false === 0
echo 'False in array';
}
Though these approaches don't use iteration explicitly, they do iterate the array data implicitly. A quick test did show that the simple foreach outperformed the other approaches here.

Answer 3

I have tried around a lot, until i came to this final result.
This is my code:
<?php
$array = array();
$array[] = true;
$array[] = false;
$array[] = false;
$array[] = true;
$array[] = false;
var_dump($array);
if((count($array)/2) <= array_sum($array)){
echo "true";
// return true
} else {
echo "false";
// return false
}
?>
it counts the elements of the array, and compares it with the COUNTED trues (array_sum($array)). Then it returns true or false, dependent on result.

Answer 4

You could iterate through the array and set a result to false if any vals are false;
$result = true;
foreach ($array as $v) {
if ($v===false) $result = false;
}

Answer 5

You can use array_filter without callback. In this case all entries of array equal to false will be removed.
if (count(array_filter($array)) == count($array)) echo 'TRUE';