How to search multiple keys from predefined array? - php

i have predefined array of categories like this in key => value pair
$all_categories = array (
1 => 'friends',
2 => 'family',
3 => 'personal',
4 => 'public'
);
and i have new small array like this which are only values.
$searched_categories = array('family','public');
Now how can i get the keys from $all_categories array having values as $searched_categories ?
i want output like this
$output_array = array(2,4);
i can get single key using array_search but is there a prebuilt function for this ? or i have to create a loop to array_search all the values i have ?
is this proper way of achieving this ?
$output_array = array ();
foreach ($searched_categories as $value){
$key = array_search($value, $all_categories );
$output_array = $key;
}

$all_categories = array (1 => 'friends', 2 => 'family', 3 => 'personal', 4 => 'public');
$searched_categories = array('family','public');
$output_array = array_keys(
array_intersect(
$all_categories,
$searched_categories
)
);
var_dump($output_array);

You could use a foreach loop and in_array.
foreach($all_categories as $key => $category){ //loop through your categories array
if(in_array($category, $searched_categories)){ //check if category is in searched_catgories
$output_array[] = $key; //if category is there, then save the key to your new array
}
}
print_r($output_array); will give you Array ( [0] => 2 [1] => 4 )

array_search is doing the job, but you erase your array all the time and add $key regardless of the fact it could be equal to false from array_search :
foreach ($searched_categories as $value){
$key = array_search($value, $all_categories );
if ($key !== false)
$output_array[] = $key;
}

Related

Searching in multi dimensional array using array_search

I have an array with the following setup:
array(
array(
'product_id' => 733
),
array(
'product_name' => Example
)
)
I want to check that 733 exists in my array which I need to use array_search (going by googling) as in_array doesn't work on m-d arrays.
My code is:
$key = array_search( '733', array_column( $items, 'product_id' ) );
If I var_dump the $items array I can see the product_id
I want to check the specific ID exists in the array and then perform other code.
So basically you want to check that given product-id exist in your multidimensional array or not?
You can do it like below:-
<?php
$items = array(
array(
'product_id' => 733
),
array(
'product_name' => Example
)
);
function searchForId($id, $array) {
foreach ($array as $key => $val) {
if (!empty($val['product_id']) && $val['product_id'] == $id) {
return "true"; // or return key according to your wish
}
}
return "false";
}
echo $found = searchForId(733, $items);
Output:- https://eval.in/805075
Reference taken:- https://stackoverflow.com/a/6661561/4248328

PHP Remove Multidimensional Array Value

I have array multidimensional code like this:
$array = [
'fruits' => ['apple','orange','grape', 'pineaple'],
'vegetables' => ['tomato', 'potato']
];
$eaten = 'grape';
unset($array[$eaten]);
and what i need is to delete 'grape' from the array because 'grape' already eaten. how to fix my code to unset the 'grape'?
and my question number two, if it can be unset, is there a way to unset multi value like
unset($array,['grape','orange']);
thanks for help..
You can remove eaten element by following way. Use array_search() you can find key at the position of your eaten element.
Here below code shows that in any multidimensional array you can call given function.
$array = [
'fruits' => ['apple','orange','grape', 'pineaple'],
'vegetables' => ['tomato', 'potato']
];
$eaten = 'grape';
$array = removeElement($array, $eaten);
function removeElement($data_arr, $eaten)
{
foreach($data_arr as $k => $single)
{
if (count($single) != count($single, COUNT_RECURSIVE))
{
$data_arr[$k] = removeElement($single, $eaten);
}
else
{
if(($key = array_search($eaten, $single)) !== false)
{
unset($data_arr[$k][$key]);
}
}
}
return $data_arr;
}
P.S. Please note that you can unset() multiple elements in single call. But the way you are using unset is wrong.
Instead of using unset() i suggest you to create a new Array after removal of required value benefit is that, your original array will remain same, you can use it further:
Example:
// your array
$yourArr = array(
'fruits'=>array('apple','orange','grape', 'pineaple'),
'vegetables'=>array('tomato', 'potato')
);
// remove array that you need
$removeArr = array('grape','tomato');
$newArr = array();
foreach ($yourArr as $key => $value) {
foreach ($value as $finalVal) {
if(!in_array($finalVal, $removeArr)){ // check if available in removal array
$newArr[$key][] = $finalVal;
}
}
}
echo "<pre>";
print_r($newArr);
Result:
Array
(
[fruits] => Array
(
[0] => apple
[1] => orange
[2] => pineaple
)
[vegetables] => Array
(
[0] => potato
)
)
Explanation:
Using this array array('grape','tomato'); which will remove the value that you define in this array.
This is how I would do it.
$array = [
'fruits' => ['apple','orange','grape', 'pineaple'],
'vegetables' => ['tomato', 'potato']
];
$unset_item = 'grape';
$array = array_map(function($items) use ($unset_item) {
$found = array_search($unset_item, $items);
if($found){
unset($items[$found]);
}
return $items;
}, $array);

Restructure an array

I have this array in PHP
$fields = array(
0 => array(
'field1' => 'something1',
'field2' => 'something2'
)
)
And I need it to look like this
$fields = array(
'fields1' => 'something1',
'fields2' => 'something2'
)
What function code can I use to get rid of the 0 index in the example?
You can loop through like this...
Create new array
$newArray = [];
Then loop through
foreach($fields as $field){
if(is_array($field)){
foreach($field as $key => $value){
$newArray[$key] = $value;
}
}
}
just take the '0' element from fields:
$fields=$fields[0];
Simple
$fields = reset($fields);
Or
$fields = array_shift($fields);
Create an array, loop through $fields, and merge whatever items are there with the created array.
$final_array = array();
foreach ($fields as $field)
{
$final_array = array_merge($final_array, $field);
}
$fields = $final_array;
This will be able to handle any number of items in either level of the array and compact them into a one-level array.
$it = new RecursiveIteratorIterator(new RecursiveArrayIterator($data)); $list = iterator_to_array($it,false);
Use this to get ride of any extra levels.
Will gives you what you want

Build multidimensional array from an array in PHP

I would like to build a multidimensional array from an array. For example I would like
$test = array (
0 => 'Tree',
1 => 'Trunk',
2 => 'Branch',
3 => 'Limb',
4 => 'Apple',
5 => 'Seed'
);
to become
$test =
array (
'Tree' => array (
'Trunk' => array (
'Branch' => array (
'Limb' => array (
'Apple' => array (
'Seed' => array ()
)
)
)
)
)
);
or more simply
$result[Tree][Trunk][Branch][Limb][Apple][Seed] = null;
I'm trying to do this with a recursive function but i'm hitting memory limit so I'm clearly doing it wrong.
<?php
$test = array (
0 => 'Tree',
1 => 'Trunk',
2 => 'Branch',
3 => 'Limb',
4 => 'Apple',
5 => 'Seed'
);
print_r($test);
print "results of function";
print_r(buildArray($test));
function buildArray (&$array, &$build = null)
{
if (count($array) > 0)
{
//create an array, pass the array to itself removing the first value
$temp = array_values($array);
unset ($temp[0]);
$build[$array[0]] = $temp;
buildArray($build,$temp);
return $build;
}
return $build;
}
Here's an approach with foreach and without recursion, which works:
function buildArray($array)
{
$new = array();
$current = &$new;
foreach($array as $key => $value)
{
$current[$value] = array();
$current = &$current[$value];
}
return $new;
}
[ Demo ]
Now your function... first, using $build[$array[0]] without defining it as an array first produces an E_NOTICE.
Second, your function is going into infinite recursion because you are not actually modifying $array ($temp isn't the same), so count($array) > 0 will be true for all of eternity.
And even if you were modifying $array, you couldn't use $array[0] anymore, because you unset that, and the indices don't just slide up. You would need array_shift for that.
After that, you pass $build and $temp to your function, which results in further because you now you assign $build to $temp, therefore creating another loop in your already-infinitely-recurring loop.
I was trying to fix all of the above in your code, but eventually realized that my code was now pretty much exactly the one from Pevara's answer, just with different variable names, so... that's that.
This function works recursively and does the trick:
function buildArray($from, $to = []) {
if (empty($from)) { return null; }
$to[array_shift($from)] = buildArray($from, $to);
return $to;
}
In your code I would expect you see an error. You are talking to $build in your first iteration as if it where an array, while you have defaulted it to null.
It seems to be easy
$res = array();
$i = count($test);
while ($i)
$res = array($test[--$i] => $res);
var_export($res);
return
array ( 'Tree' => array ( 'Trunk' => array ( 'Branch' => array ( 'Limb' => array ( 'Apple' => array ( 'Seed' => array ( ), ), ), ), ), ), )
Using a pointer, keep re-pointing it deeper. Your two output examples gave array() and null for the deepest value; this gives array() but if you want null, replace $p[$value] = array(); with $p[$value] = $test ? array() : null;
$test = array(
'Tree',
'Trunk',
'Branch',
'Limb',
'Apple',
'Seed'
);
$output = array();
$p = &$output;
while ($test) {
$value = array_shift($test);
$p[$value] = array();
$p = &$p[$value];
}
print_r($output);

Loop through a multi dimensional array checking a specific key for repeat values in PHP

I have a multi dimensional array that I have got from a database and I want to check this array for duplicate data and store it in another array of duplicates. my code is as follows
//create temp array
$tmp = array();
foreach ($matchingarray as $nameKey => $match) {
// loop through and stoe the contents of that array to another so i can compare
$tmp[] = $match;
}
// create an array to store duplicates
$duplicatesArray = array();
// if the temp array is not empty then loop through both arrays
if (! empty($tmp)) {
foreach ($tmp as $key => $tmpvalue) {
foreach ($matchingarray as $key => $match) {
// if a key name is the same in both arrays then add it tothe duplicates array
if ($tmpvalue['name'] == $match['name']) {
$duplicatesArray = $match;
}
}
}
}
//count how many are duplicates
$dups = count($duplicatesArray);
What I would like to know is this the right logic?
I will take where Igoel left off
there is 1 error and also 1 suggest that i will make.
Error:
you cannot reuse $key twice in the foreach because they will override.
Suggestion as what Igoel stated: your best bet for duplicate effectively is to use sql. SQL is faster at processing than looping through arrays. Don't forget you need to load the data into memory and thats costly.
Try this way
<?php
static $cnt = array();
$min = 1;
$coll = array(
'dep1' => array(
'fy' => array('john', 'johnny', 'victor'),
'sy' => array('david', 'arthur'),
'ty' => array('sam', 'joe', 'victor')
),
'dep2' => array(
'fy' => array('natalie', 'linda', 'molly'),
'sy' => array('katie', 'helen', 'sam', 'ravi', 'vipul'),
'ty' => array('sharon', 'julia', 'maddy')
)
);
function recursive_search(&$v, $k){
global $cnt;
$cnt[] = $v;
}
array_walk_recursive($coll, 'recursive_search');
$newNumbers = array_filter(
array_count_values($cnt),
function ($value) use($min) {
return ($value > $min);
}
);
echo "Values > 1 are repeated \n";
print_r(array_count_values($cnt));
echo "Values repeted\n";
print_r($newNumbers);
DEMO

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