That's true. My fault. I forgot the recrusion call ;-)
I think that is the better solution so far, and it is far far away (better)
that the one you posted at first
On 01/07/2008, David Sky <espaiz@xxxxxxxxx> wrote:
>
> Hey,
>
> Can't use your example, as you check weather
> $sorted is empty, if it is -> run the foreach and return,
> but on next recursion when it's not empty - do nothing :)
>
> Though I found how to cut a few seconds (on very big array),
> removing the first if, and adding a $return=true to functions'
> parameters, and in future calls set it to false:
>
> function recur($array, &$sorted=array(), $pid=0, $level=0, $return=true)
>
> {
> foreach($array as $id=>$parent)
> {
> if($pid===$parent)
> {
> $sorted[$id]= $level;
> unset($array[$id]);
> if(in_array($id,$array)){
>
> recur($array, &$sorted, $id,
> $level+1, false);
> }
> }
> }
> if($return){return $sorted;}
> }
>
>
> Well, I guess that's it, I'm sure I can think of
> another way to cut execution time, but, well,
> I don't have much time for it :)
>
>
> Thanks all!
>
> David.
>
>
> On Mon, Jun 30, 2008 at 8:24 AM, Roberto Costumero Moreno
>
> <rcostu@xxxxxxxxx> wrote:
> > Hi David,
> >
> > That's good work ;-)
> >
> > You are right that my example would only return one entry for each
> parent.
> > Didn't realized of that.
> >
> > I know the local copies you create in the recursive calls is not the best
> > solution in efficiency, but lots of times it is better to have local
> copies
> > of the array (in time of execution of the foreach) that the reference to
> it,
> > and the loss is not so big.
> >
> > I think i would not be able to improve that function a lot, but if I come
> up
> > a solution I will tell you.
> >
> > One little advice, you can get the same functionality saving a little bit
> of
> > code, and having one variable less, so the function should look like this
> > (avoiding the use of $return variable and makes the code clearer for
> later
> > revisions):
> >
> > /**
> > * Recursion
> > * @array as ( id => parent )
> > * return array as ( id => level ) maintaining arrays' initial order
> > */
> > function recur($array, &$sorted=array(), $pid=0, $level=0)
> > {
> > if(empty($sorted)){
> > foreach($array as $id=>$parent)
> > {
> > if($pid===$parent)
> > {
> > $sorted[$id]= $level;
> > unset($array[$id]);
> > if(in_array($id,$array)){
> > recur($array, &$sorted, $id, $level+1);
> > }
> > }
> > }
> > return $sorted;
> > }
> > }
> >
> > Note that return $sorted is inside the if so as to avoid returning an
> empty
> > array. If you don't mind returning an empty array put it down the
> bracket.
> >
> > And thanks to you. I signed up to the mailing list only two days ago
> > (although I've been working with PHP for at least 3 years), and you are
> the
> > first person I help successfully (or almost). Don't ever regret of asking
> > problems in the mailing list and always wait about 24 hours for someone
> to
> > answer ;-)
> >
> > There are lots of people from all over the world so if the one helping
> your
> > case is in the opposite part of the world and is asleep... it takes time
> ;-)
> >
> > Cheers,
> >
> > Roberto
> >
> >
> >
> >
> > On Mon, Jun 30, 2008 at 17:38, David Sky <espaiz@xxxxxxxxx> wrote:
> >>
> >> Hey Robero,
> >>
> >> Thanks for the answer, the none recursion function is a good idea,
> >> although as provided in your example if would only return one
> >> entry from each parent it can get to and it only can get to few,
> >> depends on how the array is sorted.
> >>
> >> Basically you can make it work if you would sort the array from
> >> small to high by parent value, but in my case I will get this array
> >> pre-sorted by date, so I can't change the order.
> >>
> >> Now, about your other suggestion, yes, it will work without the
> reference.
> >> I used the reference to avoid creating "local" copies of the array.
> >>
> >> I solved the problem by removing the reference just as you said, but
> then
> >> there would be to many recursions, so I ended up with this function:
> >>
> >> /**
> >> * Recursion
> >> * @array as ( id => parent )
> >> * return array as ( id => level ) maintaining arrays' initial order
> >> */
> >> function recur($array, &$sorted=array(), $pid=0, $level=0)
> >> {
> >> if(empty($sorted)){$return=true;}else{$return=false;}
> >> foreach($array as $id=>$parent)
> >> {
> >> if($pid===$parent)
> >> {
> >> $sorted[$id]= $level;
> >> unset($array[$id]);
> >> if(in_array($id,$array)){
> >> recur($array, &$sorted, $id, $level+1);
> >> }
> >> }
> >> }
> >> if($return){return $sorted;}
> >> }
> >>
> >> Checking with in_array if parent exist in array to make
> >> less runs and saving micro seconds on return... haha.
> >>
> >> I couldn't make it any faster, but if anybody can,
> >> please, let me know, I would be happy to know how to.
> >>
> >>
> >> Thanks Robero, this is first time I'm looking for help in mailing list,
> >> and I was starting to regret writing here, but your reply changed it :)
> >>
> >> Thanks!
> >>
> >> David.
> >>
> >>
> >>
> >> On Mon, Jun 30, 2008 at 6:36 AM, Roberto Costumero Moreno
> >> <rcostu@xxxxxxxxx> wrote:
> >> > That's not the problem. Look that the function is called with
> &$return,
> >> > so
> >> > there is a reference to the variable in which the function returns the
> >> > value
> >> > (if not there would not be an answer...).
> >> >
> >> > Otherwise, i think the problem is in the recursive call inside the
> >> > function.
> >> > Once you make the unset, you make a recursive call to the function
> like:
> >> >
> >> > recrusion(&$array, &$return, $id, $level+1);
> >> >
> >> > while I think the problem will be solved if you make the call just
> like:
> >> >
> >> > recrusion($array, &$return, $id, $level+1);
> >> >
> >> >
> >> > Notice that the $array variable has not & symbol, so is the variable
> >> > itself
> >> > and not a reference of it.
> >> >
> >> > Although there is a better and simple solution for that problem (or I
> >> > think
> >> > something like this should work well):
> >> >
> >> >
> >> > <?php
> >> > function recrusion($array, $return, $pid=0, $level=0){
> >> > foreach($array as $id=>$parent){
> >> > if( $parent===$pid ){
> >> > $return[$id]= $level;
> >> > unset($array[$id]); /* remove this to get
> correct
> >> > results */
> >> >
> >> > $level++;
> >> > $pid = $id;
> >> > }
> >> > }
> >> > }
> >> > $return= array();
> >> > $array= array(1=>0,2=>1,3=>2,4=>3,5=>2,6=>2,7=>6,8=>6,9=>0,10=>0);
> >> > recrusion($array, &$return);
> >> >
> >> > var_dump( $return );
> >> > ?>
> >> >
> >> > So you don't make any recursive call, you don't lose too much
> efficiency
> >> > and
> >> > it should work well for the whole array.
> >> >
> >> > Try the two solutions above and see whether if any is up to your
> >> > problem.
> >> >
> >> >
> >> > Cheers,
> >> >
> >> > Roberto
> >> >
> >> >
> >> > On Mon, Jun 30, 2008 at 14:27, Jason Norwood-Young
> >> > <jason@xxxxxxxxxxxxxxxxxxx> wrote:
> >> >>
> >> >> On Sun, 2008-06-29 at 18:25 -0800, David Sky wrote:
> >> >> > Hello everyone!
> >> >> >
> >> >> > A couple of days ago I submitted a bug to PHP
> >> >> > http://bugs.php.net/bug.php?id=45385
> >> >> > But I was mistaken, apparently it's not a bug.
> >> >> > And I was "sent" here to get help.
> >> >>
> >> >> I think you might be forgetting to return $return.
> >> >>
> >> >> J
> >> >>
> >> >>
> >> >> --
> >> >> PHP General Mailing List (http://www.php.net/)
> >> >> To unsubscribe, visit: http://www.php.net/unsub.php
> >> >>
> >> >
> >> >
> >
> >
>
