PYTHON array_slice

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Python replacement for PHP's array_slice [ edit | history ]
Use the slice syntax for sequences:
array[offset : offset+length]


input = ["a", "b", "c", "d", "e"]

output = input[2:] # returns ["c", "d", "e"]
output = input[-2:-1] # returns ["d"]
output = input[:3] # returns ["a", "b", "c"]


More flexible function
def array_slice( array , offset , length = None ):
	if is_array( array ) and not isinstance( array , dict ):
		if isinstance( array , set ):
			array = list( array )
			return set( array[offset:length] )
		return array[offset:length]
	return False

PHP array_slice

PHP original manual for array_slice [ show | php.net ]

array_slice

(PHP 4, PHP 5)

array_sliceExtract a slice of the array

Description

array array_slice ( array $array , int $offset [, int $length [, bool $preserve_keys= false ]] )

array_slice() returns the sequence of elements from the array array as specified by the offset and length parameters.

Parameters

array

The input array.

offset

If offset is non-negative, the sequence will start at that offset in the array . If offset is negative, the sequence will start that far from the end of the array .

length

If length is given and is positive, then the sequence will have that many elements in it. If length is given and is negative then the sequence will stop that many elements from the end of the array. If it is omitted, then the sequence will have everything from offset up until the end of the array .

preserve_keys

Note that array_slice() will reorder and reset the array indices by default. You can change this behaviour by setting preserve_keys to TRUE.

Return Values

Returns the slice.

Changelog

Version Description
5.0.2 The optional preserve_keys parameter was added.

Examples

Example #1 array_slice() examples

<?php
$input 
= array("a""b""c""d""e");

$output array_slice($input2);      // returns "c", "d", and "e"
$output array_slice($input, -21);  // returns "d"
$output array_slice($input03);   // returns "a", "b", and "c"

// note the differences in the array keys
print_r(array_slice($input2, -1));
print_r(array_slice($input2, -1true));
?>

The above example will output:

Array
(
    [0] => c
    [1] => d
)
Array
(
    [2] => c
    [3] => d
)

See Also

  • array_splice() - Remove a portion of the array and replace it with something else
  • unset() - Unset a given variable