Calculate Document Frequency in Multidimensinal Array PHP

Question

I have an array like this

 Array ( 
        [0] => Array ( [id_doc] => 1 [term] => curi ) 
        [1] => Array ( [id_doc] => 1 [term] => tidur ) 
        [2] => Array ( [id_doc] => 1 [term] => kamar ) 
        [3] => Array ( [id_doc] => 2 [term] => curi ) 
        [4] => Array ( [id_doc] => 2 [term] => cela ) 
        [5] => Array ( [id_doc] => 2 [term] => hukum ) 
        [6] => Array ( [id_doc] => 3 [term] => nyanyi ) 
        [7] => Array ( [id_doc] => 3 [term] => dangdut ) 
        [8] => Array ( [id_doc] => 3 [term] => curi )   
    )

How to get count of document frequency from term that on these document. I want the output like this.

Array ( 
        [0] => Array ( [id_doc] => 1 [term] => curi [doc_frequency] => 3 ) 
        [1] => Array ( [id_doc] => 1 [term] => tidur [doc_frequency] => 1 ) 
        [2] => Array ( [id_doc] => 1 [term] => kamar [doc_frequency] => 1 ) 
        [3] => Array ( [id_doc] => 2 [term] => curi [doc_frequency] => 3 ) 
        [4] => Array ( [id_doc] => 2 [term] => cela [doc_frequency] => 1 ) 
        [5] => Array ( [id_doc] => 2 [term] => hukum [doc_frequency] => 1 ) 
        [6] => Array ( [id_doc] => 3 [term] => nyanyi [doc_frequency] => 1 ) 
        [7] => Array ( [id_doc] => 3 [term] => dangdut [doc_frequency] => 1 ) 
        [8] => Array ( [id_doc] => 3 [term] => curi [doc_frequency] => 3 )  
    )

So term 'curi' have 3 document frequency, because its appear on 3 documents. I have tried with this

$count_df = array_count_values(array_map(function($item) {
   return $item['term'];
}, $dokumen_frek));
print_r($count_df);

but the result is

Array ( 
[curi] => 3 
[tidur] => 1 
[kamar] => 1 
[cela] => 1 
[hukum] => 1 
[nyanyi] => 1 
[dangdut] => 1

)

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Use an associative array whose keys are the document names and values are the frequencies. Loop through your array, and increment the frequency of the element with the current name. Then when you're done you can add the frequencies to the original array. — Barmar, Dec 07 '17 at 19:59
Check this https://stackoverflow.com/questions/32603607/php-array-count-values-with-multidimensional-array — Ravinder Reddy, Dec 07 '17 at 20:12

score 1 · Accepted Answer · answered Dec 07 '17 at 20:06

1

Use array_count_values function

$terms = array_count_values(array_column($arr, 'term'));

foreach($arr as &$x) {
   $x['doc_frequency'] = $terms[$x['term']];
}

demo

answered Dec 07 '17 at 20:06

splash58

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Calculate Document Frequency in Multidimensinal Array PHP

1 Answers1