Take a look at this page with the documentation for array_splice, and inspect the first example.
http://www.php.net/manual/en/function.array-splice.php
It is confusing me as the following code in example 1 is not correct as far as I can tell,
$input = array("red", "green", "blue", "yellow");
array_splice($input, 2);
// $input is now array("red", "green")
When I do this on my local machine I get the following,
$array = array(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20);
array_splice($array, 10);
// $array is now array(11, 12, 13, 14, 15, 16, 17, 18, 19, 20);
On PHPs page the example returns the elements, whereas on my local machine it removes them instead?
I don't get it? Am I missing something?
Probably the documentation is wrong.
I tested your code and the code on php.net and works perfectly great, as in your example.
I am getting this:
$input = array("red", "green", "blue", "yellow");
array_splice($input, 2);
// $input is now array("blue", "yellow")
So i would say that php.net is wrong (weird!! isn't it????)
Related
Having two arrays of authRoom and partiRoom with one same value inside them. Want to find that same value if it was matched
Found array_search function that work only with single variable
$authRoom = [8, 7, 1, 22, 13, 18, 10];
$partiRoom= [3, 6, 5, 9, 8];
I want the output to be 8 which is the same value of these two arrays
You can use array_intersect which will give you an array of the same values in both $authRoom and $partiRoom like so:
$authRoom = [8, 7, 1, 22, 13, 18, 10];
$partiRoom = [3, 6, 5, 9, 8];
$res = array_intersect($authRoom, $partiRoom);
print_r($res); // [8]
If you want to get the value 8 outside of the array, you can simply access the first value using index 0:
$res = array_intersect($authRoom, $partiRoom)[0];
echo $res; // 8
I have an array with 4 elements
[1, 2, 3, 4]
So far I am printing several arrays, all with different elements in each array, to a limit set by me.
for($i = 0; $i<=100; $i++){//...
Output so far:
[11, 22, 32, 44]
[22, 33, 44, 45]
[12, 24, 25, 31]
[15, 16, 31, 41]
[22, 33, 44, 45]//already exist
[11, 22, 32, 44]//already exist
...
How can I compare an outgoing array to the next one going out and delete the new one if is equal to the previous array?
You could create a key for an array with the help of implode() and have a set array which has this key. If key is already present, then the current array in iteration is a duplicate one, else it's a new one. Remember to sort the current array as the order of the numbers matter here for proper key check.
<?php
$arr = [
[11, 22, 32, 44],
[22, 33, 44, 45],
[12, 24, 25, 31],
[15, 16, 31, 41],
[22, 33, 44, 45],
[44, 22, 32, 11]
];
$set = [];
foreach($arr as $curr_array){
sort($curr_array);
$hash = implode("|",$curr_array);
if(isset($set[$hash])) echo "Duplicate",PHP_EOL;
else{
print_r($curr_array);
$set[$hash] = true;
}
}
Demo: https://3v4l.org/EXXRu
How to generate a random from the following list of numbers-
a) 1 to 50 (one from the list)
b) 6, 12, 18, 24, 30 (one from the list)
c) 7, 13, 19, 25, 31 (one from the list)
d) 3 to 75 (one from the list)
Try following that will help you
$fixarray1 = array(6, 12, 18, 24, 30);
$fixarray2 = array(7, 13, 19, 25, 31);
$arra1 = rand(1, 50);
$arra2 = array_rand($fixarray1,1);
$arra3 = array_rand($fixarray2,1);
$arra4 = rand(3, 75);
echo $arra1."-".$arra2."-".$arra3."-".$arra4;
I have an array fetched from mysql database tables of type. I want to sort it in order of particular value.
$arr1=array(array(12, 8, 5, 34),
array(54, 87, 32, 10),
array(23, 76, 98, 13),
array(53, 16, 24, 19));
How can i sort it by value?
Like sorting by 2nd value should result to.
$arr1=array(array(12, 8, 5, 34),
array(53, 16, 24, 19),
array(23, 76, 98, 13),
array(54, 87, 32, 10));
I like to use usort to solve these problems.
$sortKey = 1;
usort($arr1, function($a, $b) use($sortKey){
return $a[$sortKey] - $b[$sortKey];
});
Got to agree with #RocketHazmat, array_multsort is a royal pain in the backside. usort is much easier to follow but I thought I'd have a go anyway:
$sortKey = 1;
array_multisort(array_map(function($v) use($sortKey){
return $v[$sortKey];
}, $arr1), $arr1);
It only took 20 minutes... :(
Here's a demo: http://ideone.com/2rZYIz
I have an array within an array, for example:
[
[0, 20, 5],
[5, 0, 15],
[5, 10, 0]
]
I need to get the max number in each column.
The max of [0 , 5 , 5] is 5, so that goes into the result array.
The max of [20, 0, 10] is 20, so that goes into the result array.
The max of [5, 15, 0] is 15, so that goes into the result array.
The final result array must contain [5, 20, 15].
First, the array has to be transposed (flip the rows and columns):
function array_transpose($arr) {
$map_args = array_merge(array(NULL), $arr);
return call_user_func_array('array_map', $map_args);
}
(taken from Is there better way to transpose a PHP 2D array? - read that question for an explanation of how it works)
Then, you can map the max function on the new array:
$maxes = array_map('max', array_transpose($arr));
Example: http://codepad.org/3gPExrhO
Output [I think this is what you meant instead of (5, 15, 20) because you said index 1 should be max of (20, 0, 10)]:
Array
(
[0] => 5
[1] => 20
[2] => 15
)
Without the splat operator, array_map() with max() will return the max value for each row. ([20, 15, 10])
With the splat operator to transpose the data structure, the max value for each column is returned.
Code: (Demo)
$array = [
[0, 20, 5],
[5, 0, 15],
[5, 10, 0]
];
var_export(
array_map('max', ...$array)
);
Output:
array (
0 => 5,
1 => 20,
2 => 15,
)