Handling Missing values

[saurabhgayali]

It would be nice if we can handle missing values. At least option to ignore to replace with number.

[markrogoyski]

Hi,

Thanks for your interest in MathPHP.

Can you be more specific and provide some examples of what you are talking about?

[saurabhgayali]

My Data has missing points and so I am getting following errors on calculating quartiles.

Fatal error: Uncaught TypeError: MathPHP\Statistics\Average::kthSmallest(): Return value must be of type float, null returned in \vendor\markrogoyski\math-php\src\Statistics\Average.php:158 Stack trace: #0 \vendor\markrogoyski\math-php\src\Statistics\Average.php(103): MathPHP\Statistics\Average::kthSmallest(Array, 2) #1 \vendor\markrogoyski\math-php\src\Statistics\Average.php(165): MathPHP\Statistics\Average::median(Array) #2 \vendor\markrogoyski\math-php\src\Statistics\Average.php(108): MathPHP\Statistics\Average::kthSmallest(Array, 2384) #3 \vendor\markrogoyski\math-php\src\Statistics\Descriptive.php(419): MathPHP\Statistics\Average::median(Array) #4 \vendor\markrogoyski\math-php\src\Statistics\Descriptive.php(355): MathPHP\Statistics\Descriptive::quartilesExclusive(Array) #5 \tempmaths.php(41): MathPHP\Statistics\Descriptive::quartiles(Array) #6 {main} thrown in \vendor\markrogoyski\math-php\src\Statistics\Average.php on line 158

Using function Descriptive::quartiles($myarray);

[markrogoyski]

Hi @saurabhgayali,

I'm not sure what you mean by "missing points" since you are not specific, but presuming you mean null values, you can easily filter your data before calling any functions.

For example:

php > $list = [1, 2, 3, null, 5, 6, null, 8, 9, 10];
php > $filteredList = array_filter($list, function (?int $item): int { return is_int($item); } );
php > print_r($filteredList);
Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [4] => 5
    [5] => 6
    [7] => 8
    [8] => 9
    [9] => 10
)

Keep in mind this is not a data science library, it is a math library. Part of data science is preparing data to do mathematical analysis on it.