Finding position of an array.

jtown

I have an array with value like ...

name1=>score
name2=>score

.....

etc.

I've sorted it so that the lowest score is at the beginning of the array. Now I'm wondering how I can display the rank of these guys when I know the name. NOTE: I know how to display the rank in order (just output the array, but I want to know the rank via the name)

thanks in advance.

jtown

anyone?

theslinky

I'm too lazy to consult the PHP manual for a better solution, but here's a quick-n-dirty way:

<?php

// define a function
function find_index($array, $name) {
    // set a counter
    $i = 0;
    // search through the array for the item
    while(list($key, $value) = each($array)) {
        if($key == $name) {
            return $i;
        }
        $i++;
    }

// not found
return false;
}

// let's use it
$rank = find_index($scoreArray, "name1");

echo: "index/rank of name1 is $rank";

?>

remember: the index/rank starts from 0. So you might want to add a 1 (or change the function to start $i from 1)

-sridhar

Weedpacket

Originally posted by jtown
I have an array with value like ...

name1=>score
name2=>score

I've sorted it so that the lowest score is at the beginning of the array. Now I'm wondering how I can display the rank of these guys when I know the name.

I'm too lazy to check the manual, but I guess something like

$ranksbyname = array_flip(array_keys($array));

echo $ranksbyname['name1'];

Would have a suitable effect.

theslinky

weedpacket's solution will work wonderfully, but it will return the score, not the index/rank.

or is it the score what you mean by "rank"?

weedpacket: in regards to a previous post: yes, I do agree with you people should use a common date format! but if the US won't even adopt the metric system, what's the use trying to change the date formats 🙂. If you ask me: we should use timestamps ... hehe

-sridhar

jtown

no I wouldn't like the score ... the score is easy to get given the name, but I want the index value in the array ... ie. 0 to some number given the key.

jtown

Originally posted by theslinky
I'm too lazy to consult the PHP manual for a better solution, but here's a quick-n-dirty way:
<?php

// define a function
function find_index($array, $name) {
    // set a counter
    $i = 0;
    // search through the array for the item
    while(list($key, $value) = each($array)) {
        if($key == $name) {
            return $i;
        }
        $i++;
    }

// not found
return false;
}

// let's use it
$rank = find_index($scoreArray, "name1");

echo: "index/rank of name1 is $rank";

?>
remember: the index/rank starts from 0. So you might want to add a 1 (or change the function to start $i from 1)

-sridhar [/B]

thanks! this may work, but there must be some function or basic fundamental I'm missing to do this ... no?

Weedpacket

Originally posted by theslinky
weedpacket's solution will work wonderfully, but it will return the score, not the index/rank.

No, it will return the index/rank. Checkitout - I'm using array_keys() in there...and the keys are the names...

jtown

Originally posted by Weedpacket

No, it will return the index/rank. Checkitout - I'm using array_keys() in there...and the keys are the names...

you're absolutely right ... it worked.

thanks so much.

edit - oh wait ... hold on.

edit2 ... yes! it worked.