How to populate sample in php machine learning library - php

Question

$samples = [[0], [5], [10], [20], [25], [18], [30]];
$labels = ['fail', 'fail', 'pass', 'pass'];
$classifier = new NaiveBayes();
$classifier->train($samples, $labels);
echo $classifier->predict([14]);
The above code is from php machine library named php ml.
The sample and label are hardcoded in the above code. What i want to do is fill the $sample array from database. But the problem i am seeing is i cannot figure it out as you can see its $sample = [[],[],[]] . Is it array with in an array? And how to populate it
I have populated the $label successfully from db.

Answer 1

$samples = [[0], [5], [10], [20], [25], [18], [30]];
This seems like $samples is an array that contains sub-arrays for each of the sample 0, 5, 10 etc.
According to the NaiveBayes for PHP, the sample paramter expects array.

Answer 2

You can use recursive iteration to flatten your array. This will work for you based on your example data.
On another note, I would try to manipulate your query to provide you the results in the proper format.
This solution creates an unnecessary tax on your resources having to iterate across your array, which I am assuming is going to be fairly large, when a proper query will eliminate the need for this altogether.
Try this:
$samples = [[0], [5], [10], [20], [25], [18], [30]];
$labels = ['fail', 'fail', 'pass', 'pass'];
$iterator = new RecursiveIteratorIterator(new RecursiveArrayIterator($samples));
$results = iterator_to_array($iterator, false);
echo '<pre>';
print_r($results);
print_r($labels);
echo '</pre>';
This will output:
Sample:
Array
(
[0] => 0
[1] => 5
[2] => 10
[3] => 20
[4] => 25
[5] => 18
[6] => 30
)
Labels
Array
(
[0] => fail
[1] => fail
[2] => pass
[3] => pass
)
Good luck!

Answer 3

That is how we can accomplish it. Thank you everyone
while($row = mysqli_fetch_assoc($result)){
array_push($samples, array($row['result_midterm']));
}