Question 288774 in PHP Question posted in
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Equivalent of R function make.unique in PHP

I need the same functionality of R function make.unique in PHP.

In R:

> dup_array = c("a", "b", "a", "c")
> make.unique(dup_array)
[1] "a"   "b"   "a.1" "c"

In PHP:

> dup_array = array("a", "b", "a", "c")
> magic_function(dup_array)

What is the magic_function?

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2

Answers


  1. 0

    You could do it like this:

    <?php
function make_unique($a) {
    $d = array_count_values($a);
    $f = array_filter($d, function($k){
        return $k>1;
    });
    $k = array_keys($f);
    for ($i=0; $i < count($a); $i++) { 
        if(in_array($a[$i],$k) && $d[$a[$i]]>0) {
            $f[$a[$i]]--;
            $n = $d[$a[$i]]-$f[$a[$i]];
            if($n>1)$a[$i] = $a[$i].".".($n-1);
        }
    }
    return $a;
}

    You can test it:

    $a = ["a","d","c","b","a","b","a","a","d","d","a"];
print_r(make_unique($a));

    And results in:

    Array
(
    [0] => a
    [1] => d
    [2] => c
    [3] => b
    [4] => a.1
    [5] => b.1
    [6] => a.2
    [7] => a.3
    [8] => d.1
    [9] => d.2
    [10] => a.4
)
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  2. 0

    Well, there are no in-built functions already for this as yet, however, you can create your own custom function for it.

    Keep track of current frequency of the element using a dictionary(associative array) and then attach the current frequency accordingly.

    <?php

function makeUnique($arr){
    $set = [];
    foreach($arr as $k => $v){
        $set[ $v ] = ($set[ $v ] ?? 0) + 1;
        $arr[ $k ] = $arr[ $k ] . ($set[ $v ] > 1 ? '.' .($set[ $v ] - 1) : '');
    }
    return $arr;
}

print_r(makeUnique($arr));

    Online Demo

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