if I give you:
$array = array(object1, object2, object3, object4);
and say, at position 2, remove all elements before this position so the end result is:
$array = array(object3, object4);
What would I do? I was looking at array_shift and array_splice to achieve what I wanted - how ever I am not sure which to use or how to use them to achieve the desired affect.
Use array_slice. For more detail check link http://php.net/manual/en/function.array-slice.php
$array = array(object1, object2, object3, object4);
$array = array_slice($array,2); // 2 is position
Or if you are looking into the values instead of the index, with a tiny adjustment in #Ashwani's answer you can have:
$array = array('object1', 'object2', 'object3', 'object4');
$slice = array_slice($array, array_search('object3',$array));
array_slice is one way to go about it, however, if you are wanting to remove all the elements in an any array before a specific value, without searching, then:
//assuming you've already verified the match is in the array
//make a copy of $array first if you don't want to break the original
while($array[0] !== $match) {
array_shift(&$array);
}
Alternatively, you could:
$index = array_search($match, array_values($array));
if($index !== false) $array = array_slice($array, $index);
This accomplished both the verification and slice. Note the array_values() is used to account for associative arrays.
Related
I have an array in the array, and I want to make it just one array, and I can easily retrieve that data
i have some like
this
but the coding only combines the last value in the first array, not all values
is it possible to make it like that?
so that I can take arrays easily
I would make use of the unpacking operator ..., combined with array_merge:
$array['test2'] = array_merge(...array_merge(...$array['test2']));
In your case you need to flatten exactly twice, if you try to do it one time too much it will fail due to the items being actual arrays themselves (from PHP's perspective).
Demo: https://3v4l.org/npnTi
Use array_merge (doc) and ... (which break array to separate arrays):
function flatten($arr) {
return array_merge(...$arr);
}
$arr = [[["AAA", "BBB"]], [["CCC"]]];
$arr = flatten(flatten($arr)); // using twice as you have double depth
In your case, $arr is $obj["test2"]. If your object is json cast it to array first and if it is a string use json_decode
Live example: 3v4l
if you have a array then you can use the below code
if(!empty($array['test2'])){
$newarray = array();
foreach ($array['test2'] as $arrayRow) {
$newarray = array_merge($newarray,$arrayRow);
}
$array['test2'] = $newarray;
}
Up front, I would like to clarify that I am not looking for a workaround to find max--I already have the solution for accomplishing that goal. What I am curious about is why max(array_push()) doesn't work.
I have an array with many values in it, and want to find the max of specific values within that array. Existing array:
$array1 = array(2,6,1,'blue','desk chair');
The basic idea is to create a new array consisting of those specified values, and then find the max of that new array. I attempted to make this effort operate all on one line:
$max = max(array_push($array2, $array1[0], $array1[1], $array1[2]));
//this doesn't work at all, since $array2 doesn't already exist, as per the PHP manual
I changed to code to first create $array2, but didn't assign values at that time, just to see if the code works.
$array2 = array();
$max = max(array_push($array2, $array1[0], $array1[1], $array1[2]));
//$array2 is populated, but $max is not assigned
The obvious solution is to assign values to $array2 at creation and then use max() by itself. I'm just curious as to why max(array_push()) doesn't find max, since compounded functions normally operate from inside to outside.
Thank you.
max needs an array to work with but array_push returns an integer and actually uses the provided array by reference, you have to do :
$array2 = array();
array_push($array2, $array1[0], $array1[1], $array1[2])
$max = max($array2);
Alternatively do:
$array2 = array($array1[0], $array1[1], $array1[2]);
$max = max($array2);
A 3rd option (though not the cleanest one):
$array2 = array();
$max = max($array2 = array_merge($array2, [$array1[0], $array1[1], $array1[2]]));
For reference, see:
http://php.net/manual/en/function.max.php
http://php.net/manual/en/function.array-push.php
You could also use array_slice():
$max = max(array_slice(
$array1,
0,
3
));
if
the values you are interested in are in a sequence
you know offset and length of the sequence
For reference, see:
http://php.net/manual/de/function.array-slice.php
http://php.net/manual/de/function.max.php
For an example, see:
https://3v4l.org/nMK1Z
is it possible that, get arrays to $value with key:
Example:
$array = Array("one"=>Array("field1"=>"value1","field2"=>"value2"),
"two"=>Array("field3"=>"value3","field4"=>"value4"));
Export arrays to value:
$first = any_main_php_function_name(0,$array);
$second = any_main_php_function_name(1,$array);
Result:
$first = Array("field1"=>"value1","field2"=>"value2");
$second = Array("field3"=>"value3","field4"=>"value4");
Basically, I wanna extract multiple array. If there is no such function (any_main_php_function_name) in PHP so How can i extract above $array.
You don't need any funtion to do that. Simply get subarrays like this:
$first = $array['one'];
$second = $array['two'];
Unless you don't know the one,two keys, then you can use array_shift to get first item (one subarray). Remember that this functions also removes returned value from root array.
array_slice does what you want
$first = array_slice($array, 0, 1);
$second = array_slice($array, 1, 1);
print_r($first);
print_r($second);
May be you can array_shift to get the element from array, Like this:
$first_element=array_shift($array);
Make sure it only removes the first element from the array and
return the value of removed element.
And if you don't want to remove the element or get the sub-array in any sequence, then you can create a function like this,
function myFunction($index,$array) {
$keys = array_keys($array);
$sub_array=$arr[$keys[$index]];
}
In above function we just get the keys in a array and then use the known index to get the sub-array using keys array.
Please check this
foreach($array["one"] as $key=>$val){
echo "key=>".$key." Values=>".$val;
}
foreach($array["true"] as $key=>$val){
echo "key=>".$key." Values=>".$val;
}
I have an array on which I did array_count_values, and then an arsort.
$a example: $a = array('ten','ten','ten','three','two',one','ten','four','four');
I want to get the first element, and tried $a[0] but this did not work.
What is the correct syntax to get the first element please?
EDIT - added array
EDIT2 - Also, underlying array not allowed to be changed because their is code following that uses the associative array...
depending on whether or not you want to alter the array, you can use array_slice() or array_shift()
you can use array_values as
$a = array_values($a);
var_dump($a[0])
Same as in your last question.
key($a); // or each() for the first key=>value pair
Or alternatively:
$k = array_keys($a);
print $k[0];
ok I used this:
$a = array('ten','ten','ten','three','two','one','ten','four','four');
$bb= array_count_values ($a);
arsort($bb);
echo reset($bb);
It only works for getting the first element...Thank you all.
These are the ways of getting the first element:
$next = $arr[0];
$next = array_shift($arr);
$next = current($arr); // if the internal cursor is at position 0
What is the fastest and easiest way to get the last item of an array whether be indexed array , associative array or multi-dimensional array?
$myArray = array( 5, 4, 3, 2, 1 );
echo end($myArray);
prints "1"
array_pop()
It removes the element from the end of the array. If you need to keep the array in tact, you could use this and then append the value back to the end of the array. $array[] = $popped_val
try this:
$arrayname[count(arrayname)-1]
I would say array_pop In the documentation: array_pop
array_pop — Pop the element off the end of array
Lots of great answers. Consider writing a function if you're doing this more than once:
function array_top(&$array) {
$top = end($array);
reset($array); // Optional
return $top;
}
Alternatively, depending on your temper:
function array_top(&$array) {
$top = array_pop($array);
$array[] = $top; // Push top item back on top
return $top;
}
($array[] = ... is preferred to array_push(), cf. the docs.)
For an associative array:
$a= array('hi'=> 'there', 'ok'=> 'then');
list($k, $v) = array(end(array_keys($a)), end($a));
var_dump($k);
var_dump($v);
Edit: should also work for numeric index arrays