Getting from array

Anon

Hey,

i dont know how to say this in proper english, so i'll explain it a bit:

i want to take the ip's from the 20 last postings made by a certain user, and work further with the 2 ip's that were most in that array...

how can i do this the best way?

thnx in advance.....

Rick

gushy

Hmm, not exactly sure what you are getting at, but I'll have a go.

I would have thought that a user wouldn't have 20 ips, most people tend to access the net from the same 2/3 computers.

Where are you storing the posts & ips? In a database? If so you can extract the data using ORDER BY and your date field and then just use the first two.

Or you need to stick them in an array and perform a sort. A bubble sort will be easiest to explain, but not very efficient.

Basically in a bubble sort you compare value 1 & 2 if 2 is smaller than one you swap them around. then you do the same with 2 & 3 and so on until you reach the end. Repeat until there are no swaps.

Hope that helps point you in the right direction.

-- Nick Gushlow.

Anon

actually this isn't a bubble sort, it's a normal sort 😉

a bubble sort will start matching at the field it stopped matching in the last loop... this is much faster (eliminates checking of allready checked values)

basic bubble sort:

for ($i=0; $i<count($array)-1; $i++) {
for ($j=0; $j<count($array)-1-$i; $j++)
if ($array[$j+1] < $array[j]) { / compare the two neighbors /
$tmp = $array[j]; / swap array[$j] and array[$j+1] /
$array[$j] = $array[$j+1];
$array[$j+1] = $tmp;
}
}

here a good page on sorting algorithms:
http://www.cs.hope.edu/~alganim/ccaa/sorts.html

but then again... why try that when php allready has it's own array sorting functions 🙂

Anon

I wanted to use count_array_values, but that one didnt turned out anything when i tried to echo for example $counted[0]

if i've got this array:

$ips = array("2.2.2.2", "2.2.2.2", "2.2.2.2", "1.1.1.1", "1.1.1.1", "4.4.4.9");

i want to retrieve the ip: 2.2.2.2 because that one is the most one in the array

(bad english, sorry, i dont know a few words 🙂)

gushy

I noticed I'd given the wrong sort as an example of a bubble sort after I posted, but you can't edit posts, and I was hopng nobody would pick up on that! Bastard!!! :-)

Rick use jeroen's sort, not mine! In fact like he says use php's built in functions, but do read up on the theory of what happens (it's always useful to know how these things work).

I'm gonna gulk sulk in the corner now and feel all stupid. :-(

-- Nick Gushlow

gushy

oh. so you're not trying to find the most recent but the most used.

Well (assuming the data is stored in a database) you can use count to find the value you are looking for.

If not pull it into an array like you have and then just walk the array and notch up a counter object. (not very neat or efficient but simple).

-- Nick Gushlow.

gushy

Jeroen:

Actually now I'm confused. I haven't used bubble sorts in about 7 years, but aren't we both right? Didn't you just put into code what I wrote in english?

-- Nick Gushlow

Anon

well.. sorta, only you didn't write that it should skip allready checked values..

personally I like the insertion sort a lot more... (bubble sort is soooooow sloooow)

but then again... a quick sort is the best 🙂
it's quick and dirty 🙂 ...

Anon

you could do something like this: (it haven't tested it, just making this up as i type 🙂)

$usage=array();
for ($i=0; $i<count($array); $i++)
{
if (!isset($usage[$array[$i]])) $usage[$array[$i]]=1;
else $usage[$array[$i]]++;
}
arsort($usage);
reset($usage);

after this you'll have an array like this:

ipadress=>usagecount
2.2.2.2=>3
1.1.1.1=>2
3.3.3.3=>1
etc, etc

you should be able to work with this 🙂
(this is pure from the head so don't rely blindly on it hehehe)