saving mysql order number

[arne2]

HI,
i have created a script that randomly creates endtimes (of a race).
So like this :

PHP Code:

$endtime1=mt_rand(1,5); 


and so on for 5times (so till $endtime5).
Endtime1 is the endtime of horse nr 1
Endtime2....................................2,...

The endtimes are written in the database in the table 'horsescores'.
(id(auto_increment),horsenr,endtime,rank).
In horsenr the number of the horse (1-5)is written. In the endtime column the endtimes are written.
I now want to write the rank (depending on the endtimes, so the horse with the smallest endtime is the winner, etcetc untill the loser (5th).
How can i do this?
I thought about selecting all horses and order them by endtime with an sql query but i don't exactly now how i can save that ordering in ranknumbers.
And maybe there is a better way?

Thank you for you help

[GJay]

the endtime and rank are the same piece of information, why do you need to store it twice?

[arne2]

because i want to make the game look real by adding an endtime into the scorebord.
But you're probably right and think i just realized what you mean.
Can i (on the scorebord), order them by endtime ASC and adding the corresponding rank in the 'rank' column?
How?
With an $i ?
And when it starts $i = 1 (so first), and use a while loop with $i++ everytime?

[GJay]

yep, sounds about right.

[arne2]

cool ! I'll try it now !
About the mt_rand
is there a way to use decimal numbers, for example an mt_rand between 9,11 and 12,23?

[Mwnciau]

I dont think so... you could do :

PHP Code:

$whole = mt_rand(10, 20);
$dec = mt_rand(0, 99);

$number = $whole . '.' . $dec; 


[Mwnciau]

extending that:

PHP Code:

function my_rand_dec($min, $max){
list ($minwhole, $mindec) = explode('.', $min, 2);
list ($maxwhole, $maxdec) = explode('.', $max, 2);
$whole = mt_rand($minwhole, $maxwhole);
$dec = mt_rand($mindec, $maxdec);
return $whole . '.' . $dec;
} 


[arne2]

thank you very much

[marek_mar]

Originally Posted by Mwnciau

extending that:

PHP Code:

function my_rand_dec($min, $max){
list ($minwhole, $mindec) = explode('.', $min, 2);
list ($maxwhole, $maxdec) = explode('.', $max, 2);
$whole = mt_rand($minwhole, $maxwhole);
$dec = mt_rand($mindec, $maxdec);
return $whole . '.' . $dec;
} 


The decimal restrictions should only apply when the random number is either $minwhole or $maxwhole. When called with for ex. 20.8 and 30.9 you won't get a 25.1

[Mwnciau]

ah yes... i see my flaw... but it will probably work for what he wants.

[marek_mar]

How about like this:

PHP Code:

<?php
function float_mt_rand($min, $max)
{
    $i = 0;
    $j = 0;
    while((int) $min != (float) $min)
    {
        $min *= 10;
        $i++;
    }
    while((int) $max != (float) $max)
    {
        $max *= 10;
        $j++;
    }
    $i = max($i, $j);

    return mt_rand($min, $max) / pow(10, $i);
}
var_dump(float_mt_rand(1.244, 93.1));
?>

The only flaw is that the numbers can't get too long unless yoy will use BCMath or GMP.

[arne2]

Hi Mwnciau & marek_mar
thank you both for your efforts in helping me
About your code, Mwnciau, when i tried it it only returned decimal numbers of .0 and .1 so( 174.1,154.1,4564.1:456465.1,......)
so that's not really what i wanted.
About your code marek_mar, seems to work perfectly random, but it prints float() and int() with it, can you delete that? Thank you (because i just want to store the value in a variable like for example $randnr=float_mt_rand(min,max); for that it should only be a number right? (sorry i'm a total noob )

Also about your code marek_mar, when i tried it (with your example numbers of min and max), i almost all the time gotnumbers 0,985 and 1,6 and never like 13.2. Why? (i don't understand your function ).
Also : i should have numbers varying between 9.12 and 14.1, should i just enter that numbers in the min and max?

THANK YOU BOTH AGAIN!

[marek_mar]

Originally Posted by arne2

About your code marek_mar, seems to work perfectly random, but it prints float() and int() with it, can you delete that? Thank you (because i just want to store the value in a variable like for example $randnr=float_mt_rand(min,max); for that it should only be a number right? (sorry i'm a total noob )

Yes, the int/float is from var_dump(). It is useful to know which type a variable has sometimes and that's why I use it.

Originally Posted by arne2

Also about your code marek_mar, when i tried it (with your example numbers of min and max), i almost all the time gotnumbers 0,985 and 1,6 and never like 13.2. Why? (i don't understand your function ).

I'm sorry this is a bug. This is version is corrected.

PHP Code:

<?php
function float_mt_rand($min, $max)
{
    $i = 0;
    while((int) $min != (float) $min || (int) $max != (float) $max)
    {
        $min *= 10;
        $max *= 10;
        $i++;
    }
    return mt_rand($min, $max) / pow(10, $i);
}
var_dump(float_mt_rand(1.244, 93.1));
?>

[thunderhoster]

This is not the best way to solve your problem (it can occasionally cause some delay) but the quickest:

<?php

function my_rand_dec($min, $max){
    $whole = 0;
    $dec = 0;
    
    $maxwhole = explode('.', $max, 2);
    $maxwhole = $maxwhole[0];
    
    $minwhole = explode('.', $min, 2);
    $minwhole = $minwhole[0];

    while (($whole . '.' . $dec) == 0 || ($whole . '.' . $dec) > $max || ($whole . '.' . $dec) < $min) {
        $whole = mt_rand($minwhole, $maxwhole);
        $dec = mt_rand(0, 99);
    }
    
    return $whole . '.' . $dec;
}

?>

[arne2]

thank you both i'm going to test it right away !
Could anyone of you comment your code because i tried but i can't really figure out what everything means.