array multisort question

[annmartinson]

yes, I've read and tried umpteen of the sort functions and still can't
get it right. which one do I need???

/////////////////////////////////////////////
here is my array:

$final[0]['name'] = "fire";
$final[0]['value'] = 0;
$final[0]['id'] = 1;
$final[0]['name'] = "air";
$final[0]['value'] = 0;
$final[0]['id'] = 2;
$final[0]['name'] = "infinity";
$final[0]['value'] = 0;
$final[0]['id'] = 3;
$final[0]['name'] = "water";
$final[0]['value'] = 0;
$final[0]['id'] = 4;
$final[0]['name'] = "earth";
$final[0]['value'] = 0;
$final[0]['id'] = 5;

Within my functional code, the 'value' keys are changed dynamically
based on returns from a form on a website. At this point, I want to
rearrange the array SORT_NUMERICAL, SORT_DESC so that the first two
records are the highest value. I then assign these two 'id' keys to
separate variables and use them to post the info requested back to the
site visitor.

I've tried
--- (1)

$final2 = arsort($final[value], SORT_NUMERIC);

$id = $final2[0]['id'];
$id2 = $final2[1]['id'];

---(2)
$final = array_multisort($final[value], SORT_NUMERIC, SORT_DESC);

$id = $final[0]['id'];
$id2 = $final[1]['id'];

---(3)
$final2 = array_multisort($final[value], SORT_NUMERIC, SORT_DESC,
$final[key]);

$id = $final2[0]['id'];
$id2 = $final2[1]['id'];
every one of these gave me various errors.

help is much appreciated. I'm sure the answer is MUCH simpler than I'm
managing :)

[annmartinson]

SORRY, here is the correct array ... that's not the problem.

$final[0]['name'] = "fire";
$final[0]['value'] = 0;
$final[0]['id'] = 1;
$final[1]['name'] = "air";
$final[1]['value'] = 0;
$final[1]['id'] = 2;
$final[2]['name'] = "infinity";
$final[2]['value'] = 0;
$final[2]['id'] = 3;
$final[3]['name'] = "water";
$final[3]['value'] = 0;
$final[3]['id'] = 4;
$final[4]['name'] = "earth";
$final[4]['value'] = 0;
$final[4]['id'] = 5;

----------------------------------------------------------------
an**********@gmail.com wrote:

yes, I've read and tried umpteen of the sort functions and still can't
get it right. which one do I need???

/////////////////////////////////////////////
here is my array:

$final[0]['name'] = "fire";
$final[0]['value'] = 0;
$final[0]['id'] = 1;
$final[0]['name'] = "air";
$final[0]['value'] = 0;
$final[0]['id'] = 2;
$final[0]['name'] = "infinity";
$final[0]['value'] = 0;
$final[0]['id'] = 3;
$final[0]['name'] = "water";
$final[0]['value'] = 0;
$final[0]['id'] = 4;
$final[0]['name'] = "earth";
$final[0]['value'] = 0;
$final[0]['id'] = 5;

Within my functional code, the 'value' keys are changed dynamically
based on returns from a form on a website. At this point, I want to
rearrange the array SORT_NUMERICAL, SORT_DESC so that the first two
records are the highest value. I then assign these two 'id' keys to
separate variables and use them to post the info requested back to the
site visitor.

I've tried
--- (1)

$final2 = arsort($final[value], SORT_NUMERIC);

$id = $final2[0]['id'];
$id2 = $final2[1]['id'];

---(2)
$final = array_multisort($final[value], SORT_NUMERIC, SORT_DESC);

$id = $final[0]['id'];
$id2 = $final[1]['id'];

---(3)
$final2 = array_multisort($final[value], SORT_NUMERIC, SORT_DESC,
$final[key]);

$id = $final2[0]['id'];
$id2 = $final2[1]['id'];
every one of these gave me various errors.

help is much appreciated. I'm sure the answer is MUCH simpler than I'm
managing :)

[Rik]

an**********@gmail.com wrote:

an**********@gmail.com wrote:

>yes, I've read and tried umpteen of the sort functions and still
can't get it right. which one do I need???

/////////////////////////////////////////////
here is my array:

$final[0]['name'] = "fire";
$final[0]['value'] = 0;
$final[0]['id'] = 1;
$final[0]['name'] = "air";
$final[0]['value'] = 0;
$final[0]['id'] = 2;

Within my functional code, the 'value' keys are changed dynamically
based on returns from a form on a website. At this point, I want to
rearrange the array SORT_NUMERICAL, SORT_DESC so that the first two
records are the highest value. I then assign these two 'id' keys to
separate variables and use them to post the info requested back to
the site visitor.

I've tried
--- (1)

$final2 = arsort($final[value], SORT_NUMERIC);

$id = $final2[0]['id'];
$id2 = $final2[1]['id'];

---(2)
$final = array_multisort($final[value], SORT_NUMERIC, SORT_DESC);

$id = $final[0]['id'];
$id2 = $final[1]['id'];

---(3)
$final2 = array_multisort($final[value], SORT_NUMERIC, SORT_DESC,
$final[key]);

$id = $final2[0]['id'];
$id2 = $final2[1]['id'];
every one of these gave me various errors.

help is much appreciated. I'm sure the answer is MUCH simpler than
I'm managing :)

<?php

$final[0]['name'] = "fire";
$final[0]['value'] = 0;
$final[0]['id'] = 1;
$final[1]['name'] = "air";
$final[1]['value'] = 2;
$final[1]['id'] = 2;
$final[2]['name'] = "infinity";
$final[2]['value'] = 6;
$final[2]['id'] = 3;
$final[3]['name'] = "water";
$final[3]['value'] = 1;
$final[3]['id'] = 4;
$final[4]['name'] = "earth";
$final[4]['value'] = 10;
$final[4]['id'] = 5;

function cmp($a, $b){
if($a['value']==$b['value']) return 0;
return ($a['value']>$b['value']) ? -1 : 1;
}
usort($final,'cmp');
print_r($final);
?>
--
Grtz,

Rik Wasmus

[annmartinson]

No idea why this works, but I do appreciate it very much. plugged it
in, works like a charm. thanks!!

[Rik]

an**********@gmail.com wrote:

No idea why this works, but I do appreciate it very much. plugged it
in, works like a charm. thanks!!

Well for future reference, you may need another sort, so a short
explanation:
usort($array,'function_name');

function_name is the custom name of a function to sort by. This function
will get 2 variables to compare, $a and $b, which are 2 values from your
array, so in this case:

$a = array('id'=>1,'name'=>'fire,'value'=>0);
Likewise for b.

This function will have to return either:
0 when sorting should return equals.
-1 when $a should go before $b
1 when $a should come after $b

Now we only want to sort on the 'value' key, so we in the function we only
compare the 'value' key of 'a' and 'b'. In normal sorting, the whole array
$a and $b are compared.

Grtz,
--
Rik Wasmus