RE: [PHP] Array differences
At 9:37 AM -0600 4/14/10, Ashley M. Kirchner wrote: No because that only does a one-way comparison. It only tells me what's missing from $array2. I need it from both arrays. That's why I'm comparing 1 versus 2, then 2 versus 1, and then doing a merge/unique on the result. -snip- $array1 = array(1, 2, 3, 4, 5, 6); $array2 = array(1, 3, 2, 8, 9); $diff1 = array_diff($array1, $array2); $diff2 = array_diff($array2, $array1); $result = array_unique(array_merge($diff1, $diff2)); => (4, 5, 6, 8, 9) This second $result is what I want. So far I haven't noticed any problems doing it this way ... yet. I'm sure someone will tell me otherwise. Ash Ash: Looks good to me. But note the indexes of the result. You might want to: $array1 = array(1, 2, 3, 4, 5, 6, 7, 7, 7, 7); $array2 = array(1, 2, 3, 8, 9); $diff1 = array_diff($array1, $array2); $diff2 = array_diff($array2, $array1); $diff1 = array_unique($diff1); $diff2 = array_unique($diff2); $result = array_merge($diff1, $diff2); Cheers, tedd -- --- http://sperling.com http://ancientstones.com http://earthstones.com -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
RE: [PHP] Array differences
> -Original Message- > From: lala [mailto:l...@mail.theorb.net] > Sent: Wednesday, April 14, 2010 10:15 AM > To: Ashley M. Kirchner > Cc: php-general@lists.php.net > Subject: Re: [PHP] Array differences > > Ashley M. Kirchner wrote: > > > > $array1 = array(1, 2, 3, 4, 5, 6); > > $array2 = array(1, 3, 2, 8, 9); > > $diff1 = array_diff($array1, $array2); > > $diff2 = array_diff($array2, $array1); > > $result = array_unique(array_merge($diff1, $diff2)); > > > > => (4, 5, 6, 8, 9) > > Hi Ash, > > Isn't the array_unique() unnecessary? > > Mike Thinking about it, it should be unnecessary, but at the same time I want to absolutely sure that I get unique values out of the two diffs. Ash -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Array differences
Ashley M. Kirchner wrote: $array1 = array(1, 2, 3, 4, 5, 6); $array2 = array(1, 3, 2, 8, 9); $diff1 = array_diff($array1, $array2); $diff2 = array_diff($array2, $array1); $result = array_unique(array_merge($diff1, $diff2)); => (4, 5, 6, 8, 9) Hi Ash, Isn't the array_unique() unnecessary? Mike -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
RE: [PHP] Array differences
No because that only does a one-way comparison. It only tells me what's
missing from $array2. I need it from both arrays. That's why I'm comparing
1 versus 2, then 2 versus 1, and then doing a merge/unique on the result.
$array1 = array(1, 2, 3, 4, 5, 6);
$array2 = array(1, 3, 2, 8, 9);
$result = array_diff(array_unique($array1 + $array2),
array_intersect($array1, $array2));
=> (4, 5, 6)
Versus:
$array1 = array(1, 2, 3, 4, 5, 6);
$array2 = array(1, 3, 2, 8, 9);
$diff1 = array_diff($array1, $array2);
$diff2 = array_diff($array2, $array1);
$result = array_unique(array_merge($diff1, $diff2));
=> (4, 5, 6, 8, 9)
This second $result is what I want. So far I haven't noticed any problems
doing it this way ... yet. I'm sure someone will tell me otherwise.
Ash
> -Original Message-
> From: Ryan Sun [mailto:ryansu...@gmail.com]
> Sent: Wednesday, April 14, 2010 8:45 AM
> To: a...@ashleysheridan.co.uk
> Cc: Ashley M. Kirchner; php-general@lists.php.net
> Subject: Re: [PHP] Array differences
>
> Maybe this one works?
> array_diff(array_unique($array1 + $array2), array_intersect($array1,
> $array2))
>
> On Wed, Apr 14, 2010 at 4:39 AM, Ashley Sheridan
> wrote:
> > On Tue, 2010-04-13 at 23:01 -0600, Ashley M. Kirchner wrote:
> >
> >> I have the following scenario:
> >>
> >>
> >>
> >> $array1 = array("12", "34", "56", "78", "90");
> >>
> >> $array2 = array("12", "23", "56", "78", "89");
> >>
> >>
> >>
> >> $result = array_diff($array1, $array2);
> >>
> >>
> >>
> >> print_r($result);
> >>
> >>
> >>
> >>
> >>
> >> This returns:
> >>
> >>
> >>
> >> Array
> >>
> >> (
> >>
> >> [1] => 34
> >>
> >> [4] => 90
> >>
> >> )
> >>
> >>
> >>
> >>
> >>
> >> However what I really want is a two-way comparison. I want elements
> that
> >> don't exist in either to be returned:
> >>
> >>
> >>
> >> 34 and 90 because they don't exist in $array2, AND 23 and 89 because
> they
> >> don't exist in $array1. So, is that a two step process of first
> doing an
> >> array_diff($array1, $array2) then reverse it by doing
> array_diff($array2,
> >> $array1) and merge/unique the results? Any caveats with that?
> >>
> >>
> >>
> >> $array1 = array("12", "34", "56", "78", "90");
> >>
> >> $array2 = array("12", "23", "56", "78", "89");
> >>
> >>
> >>
> >> $diff1 = array_diff($array1, $array2);
> >>
> >> $diff2 = array_diff($array2, $array1);
> >>
> >>
> >>
> >> $result = array_unique(array_merge($diff1, $diff2));
> >>
> >>
> >>
> >> print_r($result);
> >>
> >>
> >>
> >>
> >>
> >> -- A
> >>
> >
> >
> > I don't see any problems with doing it that way. This will only work
> as
> > you intended if both arrays have the same number of elements I
> believe,
> > otherwise you might end up with a situation where your final array
> has
> > duplicates of the same number:
> >
> > $array1 = $array(1, 2, 3, 4, 5, 6);
> > $array2 = $aray(1, 3, 2, 5);
> >
> > Thanks,
> > Ash
> > http://www.ashleysheridan.co.uk
> >
> >
> >
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Re: [PHP] Array differences
Maybe this one works?
array_diff(array_unique($array1 + $array2), array_intersect($array1, $array2))
On Wed, Apr 14, 2010 at 4:39 AM, Ashley Sheridan
wrote:
> On Tue, 2010-04-13 at 23:01 -0600, Ashley M. Kirchner wrote:
>
>> I have the following scenario:
>>
>>
>>
>> $array1 = array("12", "34", "56", "78", "90");
>>
>> $array2 = array("12", "23", "56", "78", "89");
>>
>>
>>
>> $result = array_diff($array1, $array2);
>>
>>
>>
>> print_r($result);
>>
>>
>>
>>
>>
>> This returns:
>>
>>
>>
>> Array
>>
>> (
>>
>> [1] => 34
>>
>> [4] => 90
>>
>> )
>>
>>
>>
>>
>>
>> However what I really want is a two-way comparison. I want elements that
>> don't exist in either to be returned:
>>
>>
>>
>> 34 and 90 because they don't exist in $array2, AND 23 and 89 because they
>> don't exist in $array1. So, is that a two step process of first doing an
>> array_diff($array1, $array2) then reverse it by doing array_diff($array2,
>> $array1) and merge/unique the results? Any caveats with that?
>>
>>
>>
>> $array1 = array("12", "34", "56", "78", "90");
>>
>> $array2 = array("12", "23", "56", "78", "89");
>>
>>
>>
>> $diff1 = array_diff($array1, $array2);
>>
>> $diff2 = array_diff($array2, $array1);
>>
>>
>>
>> $result = array_unique(array_merge($diff1, $diff2));
>>
>>
>>
>> print_r($result);
>>
>>
>>
>>
>>
>> -- A
>>
>
>
> I don't see any problems with doing it that way. This will only work as
> you intended if both arrays have the same number of elements I believe,
> otherwise you might end up with a situation where your final array has
> duplicates of the same number:
>
> $array1 = $array(1, 2, 3, 4, 5, 6);
> $array2 = $aray(1, 3, 2, 5);
>
> Thanks,
> Ash
> http://www.ashleysheridan.co.uk
>
>
>
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Re: [PHP] Array differences
On 4/14/2010 2:39 AM, Ashley Sheridan wrote:
On Tue, 2010-04-13 at 23:01 -0600, Ashley M. Kirchner wrote:
$array1 = array("12", "34", "56", "78", "90");
$array2 = array("12", "23", "56", "78", "89");
$diff1 = array_diff($array1, $array2);
$diff2 = array_diff($array2, $array1);
$result = array_unique(array_merge($diff1, $diff2));
print_r($result);
I don't see any problems with doing it that way. This will only work
as you intended if both arrays have the same number of elements I
believe, otherwise you might end up with a situation where your final
array has duplicates of the same number:
$array1 = $array(1, 2, 3, 4, 5, 6);
$array2 = $aray(1, 3, 2, 5);
Wouldn't array_unique() take care of that though? Your example
above returns 4 and 6, which would be correct.
A
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Re: [PHP] Array differences
On Wed, Apr 14, 2010 at 12:03 PM, Nathan Rixham wrote: > Ashley Sheridan wrote: >> On Tue, 2010-04-13 at 23:01 -0600, Ashley M. Kirchner wrote: >>> >>> However what I really want is a two-way comparison. I want elements that >>> don't exist in either to be returned: >>> >> >> >> I don't see any problems with doing it that way. > > By some freak chance I made an array diff class about 2 weeks ago which > covers what you need. attached :) > > usage: > > $diff = new ArrayDiff( $old , $new ); > $diff->l; // deleted items > $diff->r; // inserted items > $diff->u; // unchanged items > > The script is optimised for huge arrays, thus it's slower for small > arrays than the usual array_diff but with large arrays it's quicker. > > Regards > > Nathan > > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > nice one :) i'll put it in a work-preperation folder for htmlMicroscope then, one of these days :) -- - Greetings from Rene7705, I have made some free open source webcomponents designed and written by me available through: http://code.google.com/u/rene7705/ , or http://mediabeez.ws (latest dev versions, currently offline) Personal info about me is available through http://www.facebook.com/rene7705 - -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Array differences
Ashley Sheridan wrote: > On Tue, 2010-04-13 at 23:01 -0600, Ashley M. Kirchner wrote: >> >> However what I really want is a two-way comparison. I want elements that >> don't exist in either to be returned: >> > > > I don't see any problems with doing it that way. By some freak chance I made an array diff class about 2 weeks ago which covers what you need. attached :) usage: $diff = new ArrayDiff( $old , $new ); $diff->l; // deleted items $diff->r; // inserted items $diff->u; // unchanged items The script is optimised for huge arrays, thus it's slower for small arrays than the usual array_diff but with large arrays it's quicker. Regards Nathan -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Array differences
On Tue, 2010-04-13 at 23:01 -0600, Ashley M. Kirchner wrote:
> I have the following scenario:
>
>
>
> $array1 = array("12", "34", "56", "78", "90");
>
> $array2 = array("12", "23", "56", "78", "89");
>
>
>
> $result = array_diff($array1, $array2);
>
>
>
> print_r($result);
>
>
>
>
>
> This returns:
>
>
>
> Array
>
> (
>
> [1] => 34
>
> [4] => 90
>
> )
>
>
>
>
>
> However what I really want is a two-way comparison. I want elements that
> don't exist in either to be returned:
>
>
>
> 34 and 90 because they don't exist in $array2, AND 23 and 89 because they
> don't exist in $array1. So, is that a two step process of first doing an
> array_diff($array1, $array2) then reverse it by doing array_diff($array2,
> $array1) and merge/unique the results? Any caveats with that?
>
>
>
> $array1 = array("12", "34", "56", "78", "90");
>
> $array2 = array("12", "23", "56", "78", "89");
>
>
>
> $diff1 = array_diff($array1, $array2);
>
> $diff2 = array_diff($array2, $array1);
>
>
>
> $result = array_unique(array_merge($diff1, $diff2));
>
>
>
> print_r($result);
>
>
>
>
>
> -- A
>
I don't see any problems with doing it that way. This will only work as
you intended if both arrays have the same number of elements I believe,
otherwise you might end up with a situation where your final array has
duplicates of the same number:
$array1 = $array(1, 2, 3, 4, 5, 6);
$array2 = $aray(1, 3, 2, 5);
Thanks,
Ash
http://www.ashleysheridan.co.uk
Re: [PHP] Array differences
On Wed, Apr 14, 2010 at 7:01 AM, Ashley M. Kirchner wrote:
> I have the following scenario:
>
>
>
> $array1 = array("12", "34", "56", "78", "90");
>
> $array2 = array("12", "23", "56", "78", "89");
>
>
>
> $result = array_diff($array1, $array2);
>
>
>
> print_r($result);
>
>
>
>
>
> This returns:
>
>
>
> Array
>
> (
>
> [1] => 34
>
> [4] => 90
>
> )
>
>
>
>
>
> However what I really want is a two-way comparison. I want elements that
> don't exist in either to be returned:
>
>
>
> 34 and 90 because they don't exist in $array2, AND 23 and 89 because they
> don't exist in $array1. So, is that a two step process of first doing an
> array_diff($array1, $array2) then reverse it by doing array_diff($array2,
> $array1) and merge/unique the results? Any caveats with that?
>
>
>
> $array1 = array("12", "34", "56", "78", "90");
>
> $array2 = array("12", "23", "56", "78", "89");
>
>
>
> $diff1 = array_diff($array1, $array2);
>
> $diff2 = array_diff($array2, $array1);
>
>
>
> $result = array_unique(array_merge($diff1, $diff2));
>
>
>
> print_r($result);
>
>
>
>
>
> -- A
>
>
ok, adding this to the todo-list for htmlMicroscope... ETA on delivery
of 1.3.0-final: about 2 to 3 months i'm afraid.
Gotta get a new laundromat for my home too and stuff like that :)
--
-
Greetings from Rene7705,
I have made some free open source webcomponents designed
and written by me available through:
http://code.google.com/u/rene7705/ , or
http://mediabeez.ws (latest dev versions, currently offline)
Personal info about me is available through http://www.facebook.com/rene7705
-
--
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[PHP] Array differences
I have the following scenario:
$array1 = array("12", "34", "56", "78", "90");
$array2 = array("12", "23", "56", "78", "89");
$result = array_diff($array1, $array2);
print_r($result);
This returns:
Array
(
[1] => 34
[4] => 90
)
However what I really want is a two-way comparison. I want elements that
don't exist in either to be returned:
34 and 90 because they don't exist in $array2, AND 23 and 89 because they
don't exist in $array1. So, is that a two step process of first doing an
array_diff($array1, $array2) then reverse it by doing array_diff($array2,
$array1) and merge/unique the results? Any caveats with that?
$array1 = array("12", "34", "56", "78", "90");
$array2 = array("12", "23", "56", "78", "89");
$diff1 = array_diff($array1, $array2);
$diff2 = array_diff($array2, $array1);
$result = array_unique(array_merge($diff1, $diff2));
print_r($result);
-- A
