Find occurrences of length of words in array - php

Question

I'm trying to find the number of occurrences length in array;
Here's what I've tried, but I don't know what to do after.
function instances_and_count($input) {
$arr = explode(' ', $input);
$count = 0;
$test = [];
foreach ($arr as $arr_str) {
if ($count != 0) {
$test = [$count => 'hi'];
print_r($test);
}
$count++;
}
}
$test = 'A heard you say something I know you ain\'t trying to take me homeboy.';
instances_and_count($test);
In this example, I explode a string to make an array. I need a count of let's say all words with a length of 1 which in this string it's a count of 2 (A and I); How can I do this for all lengths?

Answer 1

PHP's array functions are really useful here; we can convert our exploded array of strings to an array of string lengths using array_map and strlen, and then use array_count_values to count how many words of each length there are:
$test = 'A heard you say something I know you ain\'t trying to take me homeboy.';
$counts = array_count_values(array_map('strlen', explode(' ', $test)));
print_r($counts);
Output:
Array
(
[1] => 2
[5] => 2
[3] => 3
[9] => 1
[4] => 2
[6] => 1
[2] => 2
[8] => 1
)
Demo on 3v4l.org
Note that there is a length of 8 in this array for the "word" homeboy. This can be avoided either by stripping trailing punctuation from the string, or (better) using str_word_count to extract only whole words from the original string. For example (thanks #mickmackusa):
$test = 'I heard you say something I know you ain\'t trying to take me homeboy.';
$counts = array_count_values(array_map('strlen', str_word_count($test, 1)));
print_r($counts);
Output:
Array
(
[1] => 2
[5] => 2
[3] => 3
[9] => 1
[4] => 2
[6] => 1
[2] => 2
[7] => 1
)
Demo on 3v4l.org
If you want to output the array with keys in order, just use ksort on it first:
ksort($counts);
print_r($counts);
Output:
Array
(
[1] => 2
[2] => 2
[3] => 3
[4] => 2
[5] => 2
[6] => 1
[8] => 1
[9] => 1
)
This is not necessary for use within your application.

Answer 2

Use the length of the word as array key. For each word you are looping over, check if an array entry for that length already exists - if so, increase the value by one, otherwise initialize it with 1 at that point:
function instances_and_count($input) {
$words = explode(' ', $input);
$wordLengthCount = [];
foreach($words as $word) {
$length = strlen($word);
if(isset($wordLengthCount[$length])) {
$wordLengthCount[$length] += 1;
}
else {
$wordLengthCount[$length] = 1;
}
}
ksort($wordLengthCount);
return $wordLengthCount;
}
Result:
array (size=8)
1 => int 2
2 => int 2
3 => int 3
4 => int 2
5 => int 2
6 => int 1
8 => int 1
9 => int 1