php exclude from array

array_diff

(PHP 4 >= 4.0.1, PHP 5, PHP 7, PHP 8)

array_diff — Вычислить расхождение массивов

Описание

Список параметров

Массивы, с которыми идёт сравнение

Возвращаемые значения

Примеры

Пример #1 Пример использования array_diff()

Пример #2 Пример использования array_diff() с несовпадающими типами

$source = [new S ( ‘a’ ), new S ( ‘b’ ), new S ( ‘c’ )];
$filter = [new S ( ‘b’ ), new S ( ‘c’ ), new S ( ‘d’ )];

Примечания

Смотрите также

User Contributed Notes 27 notes

array_diff(A,B) returns all elements from A, which are not elements of B (= A without B).

You should include this in the documentation more precisely, I think.

array_diff provides a handy way of deleting array elements by their value, without having to unset it by key, through a lengthy foreach loop and then having to rekey the array.

If you want a simple way to show values that are in either array, but not both, you can use this:

I´ve been looking for a array_diff that works with recursive arrays, I´ve tried the ottodenn at gmail dot com function but to my case it doesn´t worked as expected, so I made my own. I´ve haven´t tested this extensively, but I´ll explain my scenario, and this works great at that case 😀

We got 2 arrays like these:

I realy hopes that this could help some1 as I´ve been helped a lot with some users experiences. (Just please double check if it would work for your case, as I sad I just tested to a scenario like the one I exposed)

I just came upon a really good use for array_diff(). When reading a dir(opendir;readdir), I _rarely_ want «.» or «..» to be in the array of files I’m creating. Here’s a simple way to remove them:

If you just need to know if two arrays’ values are exactly the same (regardless of keys and order), then instead of using array_diff, this is a simple method:

?>

The function returns true only if the two arrays contain the same number of values and each value in one array has an exact duplicate in the other array. Everything else will return false.

my alternative method for evaluating if two arrays contain (all) identical values:

?>

may be slightly faster (10-20%) than this array_diff method:

?>

but only when the two arrays contain the same number of values and then only in some cases. Otherwise the latter method will be radically faster due to the use of a count() test before the array_diff().

Also, if the two arrays contain a different number of values, then which method is faster will depend on whether both arrays need to be sorted or not. Two times sort() is a bit slower than one time array_diff(), but if one of the arrays have already been sorted, then you only have to sort the other array and this will be almost twice as fast as array_diff().

Basically: 2 x sort() is slower than 1 x array_diff() is slower than 1 x sort().

It’s important to note that array_diff() is NOT a fast or memory-efficient function on larger arrays.

In my experience, when I find myself running array_diff() on larger arrays (50+ k/v/pairs) I almost always realize that I’m working the problem from the wrong angle.

Typically, when reworking the problem to not require array_diff(), especially on bigger datasets, I find significant performance improvements and optimizations.

If you’re not getting a count(array_diff($a1,$a2))>0 with something similar to the following arrays should use the php.net/array_diff_assoc function instead.

There is more fast implementation of array_diff, but with some limitations. If you need compare two arrays of integers or strings you can use such function:

10x faster than array_diff

Here is some code to take the difference of two arrays. It allows custom modifications like prefixing with a certain string (as shown) or custom compare functions.

I always wanted something like this to avoid listing all the files and folders you want to exclude in a project directory.

$relevantFiles = array_diff(scandir(‘somedir’), array(‘.’, ‘..’, ‘.idea’, ‘.project));

As touched on in kitchin’s comment of 19-Jun-2007 03:49 and nilsandre at gmx dot de’s comment of 17-Jul-2007 10:45, array_diff’s behavior may be counter-intuitive if you aren’t thinking in terms of set theory.

array_diff() returns a *mathematical* difference (a.k.a. subtraction) of elements in array A that are in array B and *not* what elements are different between the arrays (i.e. those that elements that are in either A or B but aren’t in both A and B).

Drawing one of those Ven diagrams or Euler diagrams may help with visualization.

As far as a function for returning what you may be expecting, here’s one:

Resubmitting. the update for takes into account comparison issues

Computes the difference of all the arrays

I’ve found a way to bypass that. I had 2 arrays made of arrays.
I wanted to extract from the first array all the arrays not found in the second array. So I used the serialize() function:

Yes you can get rid of gaps/missing keys by using:

Note that array_diff is not equivalent to

The difference is made only on the first level. If you want compare 2 arrays, you can use the code available at https://gist.github.com/wrey75/c631f6fe9c975354aec7 (including a class with an function to patch the array)

Here the basic function:

A simple multidimentional key aware array_diff function.

Based on one lad’s code, I created following function for creating something like HTML diff. I hope it will be useful.

Hi!
I tried hard to find a solution to a problem I’m going to explain here, and after have read all the array functions and possibilities, I had to create what I think should exist on next PHP releases.

What I needed, it’s some kind of Difference, but working with two arrays and modifying them at time, not returning an array as a result with the diference itself.

so basically, I wanted to delete coincidences on both arrays.

Now, I’ve some actions to do, and I know wich one I’ve to do with the values from one array or another.
With the normal DIFF I can’t, because if I’ve an array like C=1,4, I dont know if I’ve to do the Action_A with 1 or with 4, but I really know that everything in A, will go to the Action_A and everithing in B, will go to Action_B. So same happens with 4, don’t know wich action to apply.

So a call to this will be somethin’ like:

Now, why I use it precisely?

Imagine you’ve some «Events» and some users you select when create the event, can «see» this event you create. So you «share» the event with some users. Ok?

Imagine you created and Event_A, and shared with users 1,2,3.

Now you want to modify the event, and you decide to modify the users to share it. Imagine you change it to users 2,3,4.

(numbers are users ID).

So you can manage when you are going to modify, to have an array with the IDs in DDBB ($original), and then, have another array with ID’s corresponding to the users to share after modifying ($new). Wich ones you’ve to DELETE from DDBB, and wich ones do you’ve to INSERT?

If you do a simple difference or somehow, you get somethin’ like C=1,4.
You have no clue on wich one you’ve to insert or delete.

But on this way, you can know it, and that’s why:

I hope you find it useful, and I encourage PHP «makers», to add in a not distant future, somethin’ like this one natively, because I’m shure that I’m not the first one needing something like this.

Источник

Функции для работы с массивами

Содержание

User Contributed Notes 14 notes

A simple trick that can help you to guess what diff/intersect or sort function does by name.

Example: array_diff_assoc, array_intersect_assoc.

Example: array_diff_key, array_intersect_key.

Example: array_diff, array_intersect.

Example: array_udiff_uassoc, array_uintersect_assoc.

This also works with array sort functions:

Example: arsort, asort.

Example: uksort, ksort.

Example: rsort, krsort.

Example: usort, uasort.

?>
Return:
Array ( [ 0 ] => Cero [ 1 ] => Uno [ 2 ] => Dos [ 3 ] => Cuatro [ 4 ] => Cinco [ 5 ] => Tres [ 6 ] => Seis [ 7 ] => Siete [ 8 ] => Ocho [ 9 ] => Nueve [ 10 ] => Diez )
Array ( [ 0 ] => Cero [ 1 ] => Uno [ 2 ] => Dos [ 3 ] => Tres [ 4 ] => Cuatro [ 5 ] => Cinco [ 6 ] => Seis [ 7 ] => Siete [ 8 ] => Ocho [ 9 ] => Nueve [ 10 ] => Diez )
?>

Updated code of ‘indioeuropeo’ with option to input string-based keys.

Here is a function to find out the maximum depth of a multidimensional array.

// return depth of given array
// if Array is a string ArrayDepth() will return 0
// usage: int ArrayDepth(array Array)

Short function for making a recursive array copy while cloning objects on the way.

If you need to flattern two-dismensional array with single values assoc subarrays, you could use this function:

to 2g4wx3:
i think better way for this is using JSON, if you have such module in your PHP. See json.org.

to convert JS array to JSON string: arr.toJSONString();
to convert JSON string to PHP array: json_decode($jsonString);

You can also stringify objects, numbers, etc.

Function to pretty print arrays and objects. Detects object recursion and allows setting a maximum depth. Based on arraytostring and u_print_r from the print_r function notes. Should be called like so:

I was looking for an array aggregation function here and ended up writing this one.

Note: This implementation assumes that none of the fields you’re aggregating on contain The ‘@’ symbol.

While PHP has well over three-score array functions, array_rotate is strangely missing as of PHP 5.3. Searching online offered several solutions, but the ones I found have defects such as inefficiently looping through the array or ignoring keys.

Источник

array_diff_assoc

(PHP 4 >= 4.3.0, PHP 5, PHP 7, PHP 8)

array_diff_assoc — Вычисляет расхождение массивов с дополнительной проверкой индекса

Описание

Список параметров

Массивы для сравнения

Возвращаемые значения

Примеры

Пример #1 Пример использования array_diff_assoc()

Результат выполнения данного примера:

Пример #2 Пример использования array_diff_assoc()

Результат выполнения данного примера:

Примечания

Замечание: Убедитесь, что передаёте аргументы в правильном порядке, когда сравниваете схожие массивы с большим количеством ключей. Новый массив должен быть первым.

Смотрите также

User Contributed Notes 18 notes

Works more like the original function:

an earlier post for recursive array_diff_assoc failed because isset returned false on an array element containing a null value. I updated the code so it compares null values too.

If you’re looking for a true array_diff_assoc, comparing arrays to determine the difference between two, finding missing values from both, you can use this along with array_merge.

print_r(array_diff_assoc($b,$a));
// returns
array
(
[d] => 4
)

print_r(array_merge(array_diff_assoc($a,$b),array_diff_assoc($b,$a)));
// returns
array
(
[c] => 3
[d] => 4
)

The following will recursively do an array_diff_assoc, which will calculate differences on a multi-dimensional level. This not display any notices if a key don’t exist and if error_reporting is set to E_ALL:

The direction of the arguments does actually make a difference:

To diff between n-dimensional array, juste use this :

To unset elements in an array if you know the keys but not the values, you can do:

array_diff_assoc can also be used to find the duplicates in an array

NOTE: the diff_array also removes all the duplicate values that match to the values in the second array:

// yields: array(«b»,»c») the duplicate «a» values are removed
?>

Recursive implementation accepting multiple n-level-arrays as parameters:

For recursive diff of multiple arrays, exending solution provided by Gosh.

Yet another recursive implementation, without if-else hell and with multiple parameters just like the original.

Источник

Массивы

User Contributed Notes 17 notes

For newbies like me.

Creating new arrays:-
//Creates a blank array.
$theVariable = array();

//Creates an array with elements.
$theVariable = array(«A», «B», «C»);

//Creating Associaive array.
$theVariable = array(1 => «http//google.com», 2=> «http://yahoo.com»);

//Creating Associaive array with named keys
$theVariable = array(«google» => «http//google.com», «yahoo»=> «http://yahoo.com»);

Note:
New value can be added to the array as shown below.
$theVariable[] = «D»;
$theVariable[] = «E»;

To delete an individual array element use the unset function

output:
Array ( [0] => fileno [1] => Array ( [0] => uid [1] => uname ) [2] => topingid [3] => Array ( [0] => touid [1] => Array ( [0] => 1 [1] => 2 [2] => Array ( [0] => 3 [1] => 4 ) ) [2] => touname ) )

when I hope a function string2array($str), «spam2» suggest this. and It works well

hope this helps us, and add to the Array function list

Another way to create a multidimensional array that looks a lot cleaner is to use json_decode. (Note that this probably adds a touch of overhead, but it sure does look nicer.) You can of course add as many levels and as much formatting as you’d like to the string you then decode. Don’t forget that json requires » around values, not ‘!! (So, you can’t enclose the json string with » and use ‘ inside the string.)

Converting a linear array (like a mysql record set) into a tree, or multi-dimensional array can be a real bugbear. Capitalizing on references in PHP, we can ‘stack’ an array in one pass, using one loop, like this:

$node [ ‘leaf’ ][ 1 ][ ‘title’ ] = ‘I am node one.’ ;
$node [ ‘leaf’ ][ 2 ][ ‘title’ ] = ‘I am node two.’ ;
$node [ ‘leaf’ ][ 3 ][ ‘title’ ] = ‘I am node three.’ ;
$node [ ‘leaf’ ][ 4 ][ ‘title’ ] = ‘I am node four.’ ;
$node [ ‘leaf’ ][ 5 ][ ‘title’ ] = ‘I am node five.’ ;

Hope you find it useful. Huge thanks to Nate Weiner of IdeaShower.com for providing the original function I built on.

If an array item is declared with key as NULL, array key will automatically be converted to empty string », as follows:

A small correction to Endel Dreyer’s PHP array to javascript array function. I just changed it to show keys correctly:

function array2js($array,$show_keys)
<
$dimensoes = array();
$valores = array();

Made this function to delete elements in an array;

?>

but then i saw the methods of doing the same by Tyler Bannister & Paul, could see that theirs were faster, but had floors regarding deleting multiple elements thus support of several ways of giving parameters. I combined the two methods to this to this:

?>

Fast, compliant and functional 😉

//Creating a multidimensional array

/* 2. Works ini PHP >= 5.4.0 */

var_dump ( foo ()[ ‘name’ ]);

/*
When i run second method on PHP 5.3.8 i will be show error message «PHP Fatal error: Can’t use method return value in write context»

array_mask($_REQUEST, array(‘name’, ’email’));

Источник

array_udiff

array_udiff — Вычисляет расхождение массивов, используя для сравнения callback-функцию

Описание

Список параметров

Массивы для сравнения.

Callback-функция, используемая для сравнения.

Функция сравнения должна возвращать целое, которое меньше, равно или больше нуля, если первый аргумент является соответственно меньшим, равным или большим, чем второй.

Возвращаемые значения

Примеры

Пример #1 Пример использования array_udiff() с объектами класса stdClass

Результат выполнения данного примера:

Пример #2 Пример использования array_udiff() с объектами класса DateTime

// Создание календаря еженедельных встреч
$myCalendar = new MyCalendar ;

Результат выполнения данного примера:

Примечания

Смотрите также

User Contributed Notes 9 notes

I think the example given here using classes is convoluting things too much to demonstrate what this function does.

array_udiff() will walk through array_values($a) and array_values($b) and compare each value by using the passed in callback function.

Which returns the following.

Note that the compare function is used also internally, to order the arrays and choose which element compare against in the next round.

If your compare function is not really comparing (ie. returns 0 if elements are equals, 1 otherwise), you will receive an unexpected result.

I think the point being made is that array_udiff() can be used not only for comparisons between homogenous arrays, as in your example (and definitely the most common need), but it can be used to compare heterogeneous arrays, too.

Array ( [2] => Array ( [last_name] => Flagg [first_name] => Randall [phone] => 666-1000 ) )

Something interesting to note, is that the two arguments to the compare function don’t correspond to array1 and array2. That’s why there has to be logic in it to handle that either of the arguments might be pointing to the more complex employee array. (Found this out the hard way.)

Источник