new function?

Adam Maccabee Trachtenberg

22 years ago

On Tue, 13 Jan 2004, Andrey Hristov wrote:

> I know HEAD is freezed, but anyway to ask whether a new function
> in_array_all() can be added.  It works like in_array() but checks
> whether all needles are in the stack array.

Do we really need this either way?

function in_array_all($needles, $haystack, $strict = false) {
foreach($needles as $needle) {
if (!in_array($needle, $haystack, $strict)) {
return false;
}
}

return true;
}

-adam

--
adam@trachtenberg.com
author of o'reilly's php cookbook
avoid the holiday rush, buy your copy today!

Christian Schneider

22 years ago

Andrey Hristov wrote:

> It works like in_array() but checks whether all needles
> are in the stack array.

Looking at the prototype:
bool in_array_all(mixed needle1[, mixed needle2], mixed haystack [, bool
strict])

I'd say if (and I'm personally -1) this is added it should be

bool in_array_all(array needles, array haystack [, bool strict])

IMHO which would make parameter handling much simpler.

But then again you could also do array_intersect($needles, $haystack) to
get the same result in a lot of cases.

- Chris

Andrey Hristov

22 years ago

Hi Christian,

Christian Schneider wrote:

> Andrey Hristov wrote:
>
>> It works like in_array() but checks whether all needles
>> are in the stack array.
>
>
> Looking at the prototype:
> bool in_array_all(mixed needle1[, mixed needle2], mixed haystack [, bool
> strict])
>
> I'd say if (and I'm personally -1) this is added it should be
>
> bool in_array_all(array needles, array haystack [, bool strict])
>
> IMHO which would make parameter handling much simpler.
>
> But then again you could also do array_intersect($needles, $haystack) to
> get the same result in a lot of cases.
>
> - Chris
>

So, I did now some testing. Looks like in_array_all() is 6x faster than array_intersect()
the haystack is 10 elements, and needles are 3.
When 1000 elements in haystack, the fastest time (when the needles are in the beggining
in_array_all is 300x faster. When the whole haystack should be traversed it's about 250x
faster than array_intersect. When one of the needles is not in the haystack : 300x .
Script :

<?php
$i = 0;
while ($i++ < 1000) {
$a[] = $i;
}
$start = microtime(1);
$res = in_array_all(100, 2, 3, $a, true);
$end = microtime(1);
printf("Time : %3.5f\n",$end - $start);
$needles = array(100, 2, 3);
$start = microtime(1);
$diff = array_diff($needles, $a);
$end = microtime(1);
var_dump($diff);
printf("Time : %3.5f\n",$end - $start);

?>
andrey@poohie:~/dev/5_0> ./php s.php
bool(true)
Time :   0.00010
array(0) {
}
Time :   0.03888



Andrey

Andrey Hristov

22 years ago

Hi,
just a correction, I meant array_diff when i wrote array_intersect.
array_diff is more handy since just count($res)==0 is enough, $res is the
returned array of array_diff().

Andrey

Andrey Hristov wrote:

Andrei Zmievski

22 years ago

On Tue, 13 Jan 2004, Andrey Hristov wrote:

> Hi,
> just a correction, I meant array_diff when i wrote array_intersect.
> array_diff is more handy since just count($res)==0 is enough, $res is the
> returned array of array_diff().

Did you actually try array_intersect()?

- Andrei

Andrey Hristov

22 years ago

Hi Andrei :)

Andrei Zmievski wrote:

> On Tue, 13 Jan 2004, Andrey Hristov wrote:
>
>>Hi,
>>just a correction, I meant array_diff when i wrote array_intersect.
>>array_diff is more handy since just count($res)==0 is enough, $res is the
>>returned array of array_diff().
>
>
> Did you actually try array_intersect()?
>
> - Andrei
>

Here it is :
andrey@poohie:~/dev/5_0> cat s2.php
<?php
$i = 0;
while ($i++ < 1000) {
$a[] = $i;
}
$start = microtime(1);
$res = in_array_all(100, 2, 3, $a, true);
$end = microtime(1);
var_dump($res);
printf("Time : %3.5f\n",$end - $start);
$needles = array(100, 2, 3);
$start = microtime(1);
$diff = array_intersect($needles, $a);
$end = microtime(1);
var_dump($diff);
printf("Time : %3.5f\n",$end - $start);


?>andrey@poohie:~/dev/5_0> ./php s2.php
bool(true)
Time :   0.00010
array(3) {
[0]=>
int(100)
[1]=>
int(2)
[2]=>
int(3)
}
Time :   0.03078


About 300x .


Andrey

Christian Schneider

22 years ago

Hi Andrey,

My personal feeling is that not enough people use this to make the pure
speed improvement worth a new function. I guess the list will decide...

- Chris

Andrey Hristov

22 years ago

Hi,
I didn't write this function to be faster. You asked about array_intersect()
and I decided to bechmark (you didn't ask for it though). What I had in mind
when I decided to write it was to escape this :
if (in_array("some_element", $haystack) && in_array("other_element", $haystack) &&
in_array("third_element", $haystack))

which with this function will be :
in_array_all("first_element","second_element", "third_element", $haystack)

In addtion, I have no problem with the proposal the needles to be passed as an array as
first parameter. I did the current proto in the way it's now since it's more consistent
with in_array().

Finally, I hope that the list will decide.

Andrey

Christian Schneider wrote:

jason davidson

22 years ago

Andrey Hristov wrote:

> Hi,
> I didn't write this function to be faster. You asked about
> array_intersect()
> and I decided to bechmark (you didn't ask for it though). What I had
> in mind
> when I decided to write it was to escape this :
> if (in_array("some_element", $haystack) && in_array("other_element",
> $haystack) && in_array("third_element", $haystack))
>
> which with this function will be :
> in_array_all("first_element","second_element", "third_element",
> $haystack)
>
> In addtion, I have no problem with the proposal the needles to be
> passed as an array as first parameter. I did the current proto in the
> way it's now since it's more consistent with in_array().
>
> Finally, I hope that the list will decide.
>
> Andrey
>
> Christian Schneider wrote:
>
>> Hi Andrey,
>>
>> My personal feeling is that not enough people use this to make the
>> pure speed improvement worth a new function. I guess the list will
>> decide...
>>
>> - Chris
>>
>

I like the idea of passing an array of needles, I wonder if you could
just add the ability to pass a needles array to in_array, rather than
create a new function.
Anyways, it adds flexability, I would use it.

Jason

Andrey Hristov

22 years ago

Hi,

jason davidson wrote:

>
> I like the idea of passing an array of needles, I wonder if you could
> just add the ability to pass a needles array to in_array, rather than
> create a new function.
> Anyways, it adds flexability, I would use it.
>
> Jason
>

Unfortunately, in_array() cannot be modified since this will break BC.
Consider this example :
php -r '$a = array(1, 2); $haystack = array("string", array(1, 2), 5.5);
var_dump(in_array($a, $haystack));'

So, in_array() checks for everything, including arrays, starting PHP5 it can look for
objects too. So the BC is that till now an array as first parameter is quite ok therefore
it cannot be changed.


Andrey

jason davidson

22 years ago

Andrey Hristov wrote:

> Hi,
>
> jason davidson wrote:
>
>>
>> I like the idea of passing an array of needles, I wonder if you could
>> just add the ability to pass a needles array to in_array, rather than
>> create a new function.
>> Anyways, it adds flexability, I would use it.
>>
>> Jason
>>
> Unfortunately, in_array() cannot be modified since this will break BC.
> Consider this example :
> php -r '$a = array(1, 2); $haystack = array("string", array(1, 2),
> 5.5); var_dump(in_array($a, $haystack));'
>
> So, in_array() checks for everything, including arrays, starting PHP5
> it can look for objects too. So the BC is that till now an array as
> first parameter is quite ok therefore
> it cannot be changed.
>
>
> Andrey
>

Sorry, i hadnt even realized that you could already pass needles array
into in_array, and now i beleive ive missed the whole point of this
thread.. Im done.. :)

J

T.R. Cox

22 years ago

Andrey Hristov wrote:

> Hi internals,
> I know HEAD is freezed, but anyway to ask
> whether a new function in_array_all() can be added.
> It works like in_array() but checks whether all needles
> are in the stack array.
>
> Diff :
> http://www.hristov.com/andrey/projects/php_stuff/in_array_all.diff.txt
>
>
> Best wishes,
> Andrey
>

Does this mean that one of the arguments could/should be an array?

if(in_array($needles_array, $haystack_array))
{ /*err.... */ }

Cheers,
BDKR

Andrei Zmievski

22 years ago

On Tue, 13 Jan 2004, Andrey Hristov wrote:

> Hi internals,
> I know HEAD is freezed, but anyway to ask
> whether a new function in_array_all() can be added.
> It works like in_array() but checks whether all needles
> are in the stack array.
>
> Diff :
> http://www.hristov.com/andrey/projects/php_stuff/in_array_all.diff.txt

Maybe just use array_intersect() instead?

- Andrei