Remove only numeric elements from an array

Question

I have a array in this way:

$arr = array('prolongar-se', 'durante, 4, 'a', 7, 'dias', 
    'dependendo', 'da', 'dose', 'administrada', 'e', 'do', 
    'pH', 'da', 'água', 'sendo', 7.5, 'ml', 'por','cada','paciente');

I would like to remove the numerical values 4, 7 and 7.5, and return this way below:

$arr = array('prolongar-se', 'durante, 'a', 'dias', 'dependendo', 
    'da', 'dose', 'administrada', 'e', 'do', 'pH', 'da', 'água', 
    'sendo', 'ml', 'por','cada','paciente');

How can I remove elements of the numeric type of a array?

Answer 1

You can use the array_filter(), for example:

$arr = array('prolongar-se', 'durante', 4, 'a', 7, 'dias', 
    'dependendo', 'da', 'dose', 'administrada', 'e', 'do', 
    'pH', 'da', 'água', 'sendo', 7.5, 'ml', 'por','cada','paciente');

function remover_numero($string) {

    return !is_numeric($string);

}

$arr = array_filter($arr, 'remover_numero');

The array_filter expects a return of true or false, in the case of false it removes the value of the array. In the case of true it keeps. That way the remover_numero does the job of checking whether or not it is a number and then returning true if it is not numerical, or false if numerical.

You can also use something like: array_filter($arr, function($string) { return !is_numeric($string); }) which will have the same effect.

---

Upshot:

array(18) {
  [0]=>
  string(12) "prolongar-se"
  [1]=>
  string(7) "durante"
  [3]=>
  string(1) "a"
  [5]=>
  string(4) "dias"
  [6]=>
  string(10) "dependendo"
  [7]=>
  string(2) "da"
  [8]=>
  string(4) "dose"
  [9]=>
  string(12) "administrada"
  [10]=>
  string(1) "e"
  [11]=>
  string(2) "do"
  [12]=>
  string(2) "pH"
  [13]=>
  string(2) "da"
  [14]=>
  string(5) "água"
  [15]=>
  string(5) "sendo"
  [17]=>
  string(2) "ml"
  [18]=>
  string(3) "por"
  [19]=>
  string(4) "cada"
  [20]=>
  string(8) "paciente"
}

---

Test this!

Answer 2

If in your case, the numbers that are present on array always are int or float (and not a number within a string), you can make it simpler yet:

$sem_numeros = array_filter($arr, 'is_string');

Answer 3

You can make use of the function unset php to remove the array elements, but before removing, you need to check if the element is a number, a numeric string, or just a string, for this you can use the function is_numeric and finally, you need to "reindexar" the vector, since the function unset removes an element from the vector and leaves a "hole", for this, you can use the function array_values which will return all values of the vector and index it numerically.

PS: If you don’t want to remove numeric strings from the array, such as: "42", "20"..., you will need to change the function is_numeric for is_int and is_float

function removeNumberFromArray(&$array) {

    foreach($array as $key => $item) {
        if(is_numeric($item)) {
            unset($array[$key]);
        }
    }

    $array = array_values($array);
}