Group 2d array rows by identifying column value and append incremented number to the keys of subsequent group data

Question

I have a huge array coming back as search results and I want to do the following:

Walk through the array and for each record with the same "spubid" add the following keys/vals: "sfirst, smi, slast" to the parent array member in this case, $a[0]. So the result would be leave $a[0] in tact but add to it, the values from sfirst, smi and slast from the other members in the array (since they all have the same "spubid"). I think adding the key value (1, 2, 3) to the associate key (sfirst1=> "J.", smi1=>"F.", slast1=>"Kennedy") would be fine. I would then like to DROP (unset()) the rest of the members in the array with that "spubid". Here is a simplified example of the array I am getting back and in this example all records have the same "spubid":

Array ( 
  [0] => 
    Array ( 
      [spubid] => A00502 
      [sfirst] => J. 
      [smi] => A. 
      [slast] => Doe
  [1] => 
    Array ( 
      [spubid] => A00502 
      [sfirst] => J. 
      [smi] => F. 
      [slast] => Kennedy 
  [2] => 
    Array ( 
      [spubid] => A00502 
      [sfirst] => B. 
      [smi] => F. 
      [slast] => James 
  [3] => 
    Array ( 
      [spubid] => A00502
      [sfirst] => S. 
      [smi] => M. 
      [slast] => Williamson 
      )
    )

So in essence I want to KEEP $a[0] but add new keys=>values to it (sfirst$key, smi$key, slast$key) and append the values from "sfirst, smi, slast" from ALL the members with that same "spubid" then unset $a[1]-[3].

Just to clarify my IDEAL end result would be:

Array ( 
  [0] => 
    Array ( 
      [spubid] => A00502 
      [sfirst] => J. 
      [smi] => A. 
      [slast] => Doe
      [sfirst1] => J.
      [smi1] => F. 
      [slast1] => Kennedy
      [sfirst2] => B. 
      [smi2] => F. 
      [slast2] => James 
      [sfirst3] => S. 
      [smi3] => M. 
      [slast3] => Williamson
    )
  )

In most cases I will have a much bigger array to start with that includes a multitude of "spubid"'s but 99% of publications have more than one author so this routine would be very useful in cleaning up the results and making the parsing process for display much easier.

***UPDATE

I think by over simplifying my example I may have made things unclear. I like both Chacha102's and zombat's responses but my "parent array" contains A LOT more than just a pubid, that just happens to be the primary key. I need to retain a lot of other data from that record, a small portion of that is the following:

[spubid] => A00680 
[bactive] => t 
[bbatch_import] => t 
[bincomplete] => t 
[scitation_vis] => I,X 
[dentered] => 2009-08-03 12:34:14.82103 
[sentered_by] => pubs_batchadd.php 
[drev] => 2009-08-03 12:34:14.82103 
[srev_by] => pubs_batchadd.php 
[bpeer_reviewed] => t 
[sarticle] => A case study of bora-driven flow and density changes on the Adriatic shelf (January 1987)
.
.
.
.
.

There are roughly 40 columns that come back with each search query. Rather than hard coding them as these examples do with the pubid, how can I include them while still making the changes as you both suggested. Creating a multi-dimensional array (as both of you suggested) with the authors being part of the multi-dimension is perfectly fine, thank you both for the suggestion.

**** UPDATE:

Here is what I settled on for a solution, very simple and gets the job done nicely. I do end up creating a multi-dimensional array so the authors are broken out there.

Over simplified solution:

$apubs_final = array();
$spubid = NULL;
$ipub = 0;

foreach($apubs as $arec)
{
  if($spubid != $arec['spubid'])
  {
    $ipub++;
    $apubs_final[$ipub] = $arec;
    // insert UNSET statements here for author data
    $iauthor = 0;
    $spubid = $arec['spubid'];
  }
  $iauthor++;
  $apubs_final[$ipub]['authors'][$iauthor]['sauthor_first'] = $arec['sfirst'];
}

Answer 1

// First, probably the more parsable way.
foreach($array as $key => $values)
{
    $end[$spuid] = $values;
    $spuid = $values['spuid']
    $end[$spuid]['authors'][] = array('sfirst' => $values['sfirst'],
                          'smi' => $values['smi'],
                           'slast' => $values['slast']);

}

Which will get an array like this

Array(
    [A00502] =>
         Array(
           [supid] => A00502
               .... other values .....
           [authors] =>
                 Array(
                [0]=>
                      Array(
                    ['sfirst'] => '',
                    ['smi'] => '',
                    ['slast'] => '')
                )
        )
)

I find this way to be much more parse-able if you plan on showing it on a page, because it uses arrays so you can foreach the authors, which is how I've seen many people do it for attributes like that.

If you really do want your ideal format, use this afterwards

$count = 0;
foreach ($end as $supid => $values)
{
    $other_end[$count] = $values;
    $other_end[$count]['spuid'] = $spuid;
    foreach($values['authors'] as $key => $author)
    {
        if($key == 0)
        {
            $suffix = '';
        }
        else
        {
            $suffix = $key;
        }
        $other_end[$count]['sfirst'.$suffix] = $author['sfirst'];
        $other_end[$count]['smi'.$suffix] = $author['smi'];
        $other_end[$count]['slast'.$suffix] = $author['slast'];
    }

}