deleteAt: Difference between revisions
Jump to navigation
Jump to search
Lou Montana (talk | contribs) |
Lou Montana (talk | contribs) m (Text replacement - "\|seealso= *\[\[([^ ]+)\]\], \[\[([^ ]+)\]\]" to "|seealso= $1 ") |
||
Line 41: | Line 41: | ||
[[hint]] [[str]] _arr; // [1,3]</code> | [[hint]] [[str]] _arr; // [1,3]</code> | ||
|seealso= [[deleteRange]] [[set]] [[resize]] [[select]] [[in]] [[find]] | |seealso= [[deleteRange]] [[set]] [[resize]] [[select]] [[in]] [[find]] [[findIf]], [[toArray]], [[toString]], [[forEach]], [[count]], [[pushBack]], [[pushBackUnique]], [[apply]], [[append]], [[sort]], [[param]], [[params]], [[arrayIntersect]], [[splitString]], [[joinString]] | ||
}} | }} | ||
Revision as of 15:53, 20 January 2022
Description
- Description:
- Removes array element at the given index and returns removed element (modifies the original array, just like resize or set). Will not issue error when -1 index is passed making it ideal for using with find(see Example 2) or findIf(see Example 3) command
- Groups:
- ArraysHashMap
Syntax
- Syntax:
- array deleteAt index
- Parameters:
- array: Array
- index: Number
- Return Value:
- Anything - returns the deleted element
Alternative Syntax
- Syntax:
- hashMap deleteAt key
- Parameters:
- hashMap: HashMap
- key : HashMapKey
- Return Value:
- Anything
Examples
- Example 1:
_arr = [1,2,3]; _rem = _arr deleteAt 1; hint str [_rem, _arr]; //[2,[1,3]]
- Example 2:
_arr = [1,2,3]; _arr deleteAt (_arr find 0); // non existent item hint str _arr; // [1,2,3] _arr deleteAt (_arr find 2); // existent item hint str _arr; // [1,3]
- Example 3:
_arr = [1,2,3]; _arr deleteAt (_arr findIf {(_x % 5) == 0}); // Remove first number that's divisible by 5 hint str _arr; // [1,2,3] _arr deleteAt (_arr findIf {(_x % 2) == 0}); // Remove first number that's divisible by 2 hint str _arr; // [1,3]
Additional Information
- See also:
- deleteRange set resize select in find findIftoArraytoStringforEachcountpushBackpushBackUniqueapplyappendsortparamparamsarrayIntersectsplitStringjoinString
Notes
-
Report bugs on the Feedback Tracker and/or discuss them on the Arma Discord or on the Forums.
Only post proven facts here! Add Note
- Posted on October 15, 2014 - 16:55 (UTC)
- Heeeere's Johnny!
-
_array deleteAt 0
is almost 60x faster than_array = _array - [_array select 0]
(Tested with an array of 10.000 strings, iterating through it using a for-from-to-do loop) - Posted on March 4, 2016 - 15:58 (UTC)
- Highhead
- Deleting from an array with foreach and _foreachIndex variable is tricky. The array is being altered, the _foreachIndex won't keep up and other elements in the array will be skipped and in worst case not being deleted. If you delete elements from an array in descending order (using while or for) it will work.
- Posted on February 9, 2017 - 22:45 (UTC)
- Igneous01
-
To expand on Highheads comment above - this is because forEach implements iterators to traverse a collection, which are read only by definition.
The variable _x is an iterator that points to the current item in the collection. Trying to alter _x will have no effect.
ARRAY = [1,2,3,4,5,6,7,8]; { _x = 2; } forEach ARRAY // ARRAY is still [1,2,3,4,5,6,7,8]
When trying to use deleteAt inside forEach, the behaviour would be undefined as you are invalidating the iterator reference, and it will not know how to traverse to the next element. In short, only use forEach when reading data from an array. For more info about iterators, see C++ Iterators. - Posted on October 3, 2019 - 13:16 (UTC)
- Tankbuster
- The index you pass to this command is zero based. The first element is number 0 and the second is 1 etc
- Posted on February 1, 2021 - 18:06 (UTC)
- Freghar
-
As you would expect from a simple array implementation,
array deleteAt (count array - 1);
is virtually zero cost (0.0005ms on an array of 1000000 elements), whilearray deleteAt 0;
is very performance heavy (0.7ms on the same huge array).