php сумма элементов массива по ключу

Суммировать элементы столбца матрицы
#include ; #include using namespace std; int mas1.

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array_combine

array_combine — Создаёт новый массив, используя один массив в качестве ключей, а другой для его значений

Описание

Создаёт массив ( array ), используя значения массива keys в качестве ключей и значения массива values в качестве соответствующих значений.

Список параметров

Массив ключей. Некорректные значения для ключей будут преобразованы в строку ( string ).

Возвращаемые значения

Ошибки

Примеры

Пример #1 Простой пример использования array_combine()

Результат выполнения данного примера:

Смотрите также

User Contributed Notes 21 notes

If two keys are the same, the second one prevails.

But if you need to keep all values, you can use the function below:

Further to loreiorg’s script
in order to preserve duplicate keys when combining arrays.

I have modified the script to use a closure instead of create_function

Reason: see security issue flagged up in the documentation concerning create_function

// If they are not of same size, here is solution:

// Output
// Array ( [AL] => Alabama [AK] => Alaska [AZ] => Arizona
// [AR] => Arkansas )
?>

This will seem obvious to some, but if you need to preserve a duplicate key, being you have unique vars, you can switch the array_combine around, to where the vars are the keys, and this will output correctly.

This [default] formula auto-removes the duplicate keys.

This formula accomplishes the same thing, in the same order, but the duplicate «keys» (which are now vars) are kept.

I know, I’m a newbie, but perhaps someone else will need this eventually. I couldn’t find another solution anywhere.

I was looking for a function that could combine an array to multiple one, for my MySQL GROUP_CONCAT() query, so I made this function.

I needed a function that would take keys from one unequal array and combine them with the values of another. Real life application:
Select 4 product types.
Each product has a serial.
There are 4 sets of products.

Array
(
[0] => Array
(
[SMART Board] => serial to smart board1
[Projector] => serial to projector 1
[Speakers] => serial to speakers 1
[Splitter] => serials to splitter 1
)

[1] => Array
(
[SMART Board] => serials to smart board 2
[Projector] => serials to projector 2
[Speakers] => serials to speakers 2
[Splitter] => serials to splitter 2
)

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Php сумма элементов массива по ключу

В этом разделе помещены уроки по PHP скриптам, которые Вы сможете использовать на своих ресурсах.

Фильтрация данных с помощью zend-filter

Когда речь идёт о безопасности веб-сайта, то фраза «фильтруйте всё, экранируйте всё» всегда будет актуальна. Сегодня поговорим о фильтрации данных.

Контекстное экранирование с помощью zend-escaper

Обеспечение безопасности веб-сайта — это не только защита от SQL инъекций, но и протекция от межсайтового скриптинга (XSS), межсайтовой подделки запросов (CSRF) и от других видов атак. В частности, вам нужно очень осторожно подходить к формированию HTML, CSS и JavaScript кода.

Подключение Zend модулей к Expressive

Expressive 2 поддерживает возможность подключения других ZF компонент по специальной схеме. Не всем нравится данное решение. В этой статье мы расскажем как улучшили процесс подключение нескольких модулей.

Совет: отправка информации в Google Analytics через API

Предположим, что вам необходимо отправить какую-то информацию в Google Analytics из серверного скрипта. Как это сделать. Ответ в этой заметке.

Подборка PHP песочниц

Подборка из нескольких видов PHP песочниц. На некоторых вы в режиме online сможете потестить свой код, но есть так же решения, которые можно внедрить на свой сайт.

Совет: активация отображения всех ошибок в PHP

При поднятии PHP проекта на новом рабочем окружении могут возникнуть ошибки отображение которых изначально скрыто базовыми настройками. Это можно исправить, прописав несколько команд.

Агент

PHP парсер юзер агента с поддержкой Laravel, работающий на базе библиотеки Mobile Detect.

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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.

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array_keys

(PHP 4, PHP 5, PHP 7, PHP 8)

array_keys — Возвращает все или некоторое подмножество ключей массива

Описание

Список параметров

Массив, содержащий возвращаемые ключи.

Если указано, будут возвращены только ключи у которых значения элементов массива совпадают с этим параметром.

Определяет использование строгой проверки на равенство (===) при поиске.

Возвращаемые значения

Примеры

Пример #1 Пример использования array_keys()

Результат выполнения данного примера:

Смотрите также

User Contributed Notes 28 notes

It’s worth noting that if you have keys that are long integer, such as ‘329462291595’, they will be considered as such on a 64bits system, but will be of type string on a 32 bits system.

?>

will return on a 64 bits system:

but on a 32 bits system:

I hope it will save someone the huge headache I had 🙂

Here’s how to get the first key, the last key, the first value or the last value of a (hash) array without explicitly copying nor altering the original array:

Since 5.4 STRICT standards dictate that you cannot wrap array_keys in a function like array_shift that attempts to reference the array.

Invalid:
echo array_shift( array_keys( array(‘a’ => ‘apple’) ) );

But Wait! Since PHP (currently) allows you to break a reference by wrapping a variable in parentheses, you can currently use:

echo array_shift( ( array_keys( array(‘a’ => ‘apple’) ) ) );

However I would expect in time the PHP team will modify the rules of parentheses.

There’s a lot of multidimensional array_keys function out there, but each of them only merges all the keys in one flat array.

Here’s a way to find all the keys from a multidimensional array while keeping the array structure. An optional MAXIMUM DEPTH parameter can be set for testing purpose in case of very large arrays.

NOTE: If the sub element isn’t an array, it will be ignore.

output:
array(
‘Player’ => array(),
‘LevelSimulation’ => array(
‘Level’ => array(
‘City’ => array()
)
),
‘User’ => array()
)

array (size=4)
0 => string ‘e’ (length=1)
1 => int 1
2 => int 2
3 => int 0

—-
expected to see:
dude dude dude

Sorry for my english.

I wrote a function to get keys of arrays recursivelly.

Here’s a function I needed to collapse an array, in my case from a database query. It takes an array that contains key-value pairs and returns an array where they are actually the key and value.

?>

Example usage (pseudo-database code):

= db_query ( ‘SELECT name, value FROM properties’ );

/* This will return an array like so:

/* Now this array looks like:

?>

I found this handy for using with json_encode and am using it for my project http://squidby.com

This function will print all the keys of a multidimensional array in html tables.
It will help to debug when you don?t have control of depths.

An alternative to RQuadling at GMail dot com’s array_remove() function:

The position of an element.

One can apply array_keys twice to get the position of an element from its key. (This is the reverse of the function by cristianDOTzuddas.) E.g., the following may output «yes, we have bananas at position 0».

Hope this helps someone.

# array_keys() also return the key if it’s boolean but the boolean will return as 1 or 0. It will return empty if get NULL value as key. Consider the following array:

Array
(
[ 0 ] => first_index
[ 1 ] => 1
[ 2 ] => 0
[ 3 ] => 4
[ 4 ] => 08
[ 5 ] => 8
[ 6 ] =>
)

This function will extract keys from a multidimensional array

Array
(
[color] => Array
(
[1stcolor] => blue
[2ndcolor] => red
[3rdcolor] => green
)

[size] => Array
(
[0] => small
[1] => medium
[2] => large
)

Array
(
[0] => color
[1] => 1stcolor
[2] => 2ndcolor
[3] => 3rdcolor
[4] => size
[5] => 0
[6] => 1
[7] => 2
)

All the cool notes are gone from the site.

Here’s an example of how to get all the variables passed to your program using the method on this page. This prints them out so you can see what you are doing.

Simple ways to prefixing arrays;

[1] => Array
(
[product_id] => 2
[product_name] => Bar
)

I was looking for a function that deletes either integer keys or string keys (needed for my caching).
As I didn’t find a function I came up with my own solution.
I didn’t find the propiest function to post to so I will post it here, hope you find it useful.

?>

You can of course define constants to have a nicer look, I have chosen these: EXTR_INT = 1; EXTR_STRING = 2
EXTR_INT will return an array where keys are only integer while
EXTR_STRING will return an array where keys are only string

A needed a function to find the keys which contain part of a string, not equalling a string.

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