SORT_LOCALE_STRING
- compare items as strings, based on the current locale. It uses the locale, which can be changed using
setlocale()
SORT_NATURAL
- compare items as strings using "natural ordering" like
natsort()
SORT_FLAG_CASE
- can be combined (bitwise OR) with
SORT_STRING
or
SORT_NATURAL
to sort strings case-insensitively
This argument can be swapped with
array1_sort_order
or omitted entirely, in which case
SORT_REGULAR
is assumed.
rest
More arrays, optionally followed by sort order and flags. Only elements corresponding to equivalent elements in previous arrays are compared. In other words, the sort is lexicographical.
In this example, after sorting, the first array will contain 0, 10, 100, 100. The second array will contain 4, 1, 2, 3. The entries in the second array corresponding to the identical entries in the first array (100 and 100) were sorted as well.
In this example, after sorting, the first array will transform to "10", 100, 100, 11, "a" (it was sorted as strings in ascending order). The second will contain 1, 3, "2", 2, 1 (sorted as numbers, in descending order).
In this example, we will order by
volume
descending,
edition
ascending.
We have an array of rows, but
array_multisort()
requires an array of columns, so we use the below code to obtain the columns, then perform the sorting.
<?php// Obtain a list of columnsforeach($dataas$key=>$row){$volume[$key]=$row['volume'];$edition[$key]=$row['edition'];}// you can use array_column() instead of the above code$volume=array_column($data,'volume');$edition=array_column($data,'edition');// Sort the data with volume descending, edition ascending// Add $data as the last parameter, to sort by the common keyarray_multisort($volume,SORT_DESC,$edition,SORT_ASC,$data);?>
The dataset is now sorted, and will look like this:
Both
SORT_STRING
and
SORT_REGULAR
are case sensitive, strings starting with a capital letter will come before strings starting with a lowercase letter.
To perform a case insensitive sort, force the sorting order to be determined by a lowercase copy of the original array.
array_pad()
returns a copy of the
array
padded to size specified by
length
with value
value
. If
length
is positive then the array is padded on the right, if it's negative then on the left. If the absolute value of
length
is less than or equal to the length of the
array
then no padding takes place. It is possible to add at most 1048576 elements at a time.
Parameters
array
Initial array of values to pad.
length
New size of the array.
value
Value to pad if
array
is less than
length
.
Return Values
Returns a copy of the
array
padded to size specified by
length
with value
value
. If
length
is positive then the array is padded on the right, if it's negative then on the left. If the absolute value of
length
is less than or equal to the length of the
array
then no padding takes place.
Examples
Example #1
array_pad()
example
<?php$input=array(12,10,9);$result=array_pad($input,5,0);// result is array(12, 10, 9, 0, 0)$result=array_pad($input,-7,-1);// result is array(-1, -1, -1, -1, 12, 10, 9)$result=array_pad($input,2,"noop");// not padded?>
See Also
array_fill() - Fill an array with values
range() - Create an array containing a range of elements
array_push
—
Push one or more elements onto the end of array
Description
array_push(array&$array,mixed...$values):int
array_push()
treats
array
as a stack, and pushes the passed variables onto the end of
array
. The length of
array
increases by the number of variables pushed. Has the same effect as:
<?php$array[]=$var;?>
repeated for each passed value.
Note
:
If you use
array_push()
to add one element to the array, it's better to use
$array[] =
because in that way there is no overhead of calling a function.
Note
:
array_push()
will raise a warning if the first argument is not an array. This differed from the
$var[]
behaviour where a new array was created, prior to PHP 7.1.0.
Parameters
array
The input array.
values
The values to push onto the end of the
array
.
Return Values
Returns the new number of elements in the array.
Changelog
Version
Description
7.3.0
This function can now be called with only one parameter. Formerly, at least two parameters have been required.
Picks one or more random entries out of an array, and returns the key (or keys) of the random entries.
Caution
This function does not generate cryptographically secure values, and
must not
be used for cryptographic purposes, or purposes that require returned values to be unguessable.
If cryptographically secure randomness is required, the
Random\Randomizer
may be used with the
Random\Engine\Secure
engine. For simple use cases, the
random_int()
and
random_bytes()
functions provide a convenient and secure
API
that is backed by the operating system’s
CSPRNG
.
Parameters
array
The input array.
num
Specifies how many entries should be picked.
Return Values
When picking only one entry,
array_rand()
returns the key for a random entry. Otherwise, an array of keys for the random entries is returned. This is done so that random keys can be picked from the array as well as random values. If multiple keys are returned, they will be returned in the order they were present in the original array. Trying to pick more elements than there are in the array will result in an
E_WARNING
level error, and NULL will be returned.
Changelog
Version
Description
7.1.0
The internal randomization algorithm has been changed to use the » Mersenne Twister Random Number Generator instead of the libc rand function.