Hello i have two arrays one coming from the client and the other coming from my database, i want to be able to compare these two arrays and make sure they are both equal.
By equal i mean they both have the same keys and the keys have the same values:
array (size=2)
0 =>
array (size=5)
'id' => int 13
'class' => string 'Regular' (length=7)
'price' => int 100
1 =>
array (size=5)
'id' => int 13
'class' => string 'Regular' (length=7)
'price' => int 200
array (size=2)
0 =>
array (size=5)
'id' => int 13
'class' => string 'Regular' (length=7)
'price' => int 100
1 =>
array (size=5)
'id' => int 13
'class' => string 'Regular' (length=7)
'price' => int 300
In the above scenario y function shuld return false because even though my arrays have the same number of elements the price property of the second index is different, first array has 200 ad second array has 300.
Also if for some reason array 1 has more elements than array 2 then it should also return false.
What would be the best way of doing this? Bets in terms of speed and performance.
I was thinking of converting both arrays to json and checking them like a string.
Try this
$arraysAreEqual = ($a == $b); // TRUE if $a and $b have the same key/value pairs.
$arraysAreEqual = ($a === $b); // TRUE if $a and $b have the same key/value pairs in the same order and of the same types.
array_diff() is there for this purpose. And its ok if the arrays are small, but for optimization, check out this post. It involves flipping the array value and key for faster comparison. And also this other stack comment for a hash table approach.
Related
I have a multidimensional array like so:
array (size=4)
0 =>
array (size=2)
'term' => string 'news-article' (length=12)
'count' => int 139
1 =>
array (size=2)
'term' => string 'industry-resource' (length=17)
'count' => int 37
2 =>
array (size=2)
'term' => string 'editorial' (length=9)
'count' => int 33
3 =>
array (size=2)
'term' => string 'bulletin' (length=8)
'count' => int 12
and I'm trying create a function that searches for a term and returns it's neighboring value, count.
My inclination was to use array_search(), however using this returns false, I'm guessin because it's only searching the first layer of the array (0,1,2,3).
I'm not so much looking for an exact answer but a nudge in the right direction. I'm guessing it will require looping through the array, but I do not know how to approach getting the neighboring count value once the term value is located. Any help is appreciated!
You can just loop through the array and access them directly.
$search_term = "news-article";
$count = 0;
foreach($array as $element) {
if($element['term'] == $search_term) {
$count = $element['count'];
break;
}
}
I have an array like the example below (from var_dump($tagged);:
array (size=1)
0 =>
array (size=7)
0 => string '#raining' (length=8)
1 => string '#raining' (length=8)
2 => string '#driving' (length=8)
3 => string '#hungrySoon' (length=11)
4 => string '#strangeworld' (length=13)
5 => string '#fruitweekFunky' (length=15)
6 => string '#kevins_rainbow_disco' (length=21)
7 => string '#raining' (length=8)
8 => string '#fruitweekFunky' (length=15)
I am simply after displaying the array as follows (From the most frequent first):
#raining
#fruitweekFunky
#driving ...etc
To achieve exactly what you've asked for (a descending ordered array of the highest occurences to the lowest) step by step:
Count the number of occurences:
$occurences = array_count_values($tagged[0]);
Sort the array (by value, because the number of occurrences is the current array value and the tag is the key - arsort() maintains the original keys):
arsort($occurences);
Get array of the keys for output (because the tags are currently keys):
var_dump(array_keys($occurences));
Fact is, $tagged is an array of arrays. So you need to take its first element.
Try :
$result = array_count_values(array_values($tagged[0]));
var_dump($result);
This question already has answers here:
How to filter an associative array comparing keys with values in an indexed array?
(12 answers)
Closed 4 months ago.
I have following arrays:
$keys
array (size=2)
0 => string 'foo' (length=3)
1 => string 'buz' (length=3)
$data
array (size=3)
'foo' => int 1
'bar' => int 2
'buz' => int 3
How to get $data array filtered by $keys values ? Desired output:
array (size=3)
'foo' => int 1
'buz' => int 3
array_intersect_key should be able to help you out here
array_intersect_key($data, array_flip($keys));
The array_flip is needed because array_intersect_key operates on keys, so this makes sure both arrays are in the right format.
DEMO: http://codepad.org/AGpDAZtE
I have a small tricky question with nested arrays. I am getting something like that from my database:
array
0 =>
array
'id' => string '81' (length=2)
'value' => string 'foobar' (length=6)
'created_at' => string '2012-02-18 22:09:57' (length=19)
'updated_at' => string '2012-02-18 22:09:57' (length=19)
1 =>
array
'id' => string '106' (length=3)
'value' => string 'barfoo' (length=6)
'created_at' => string '2012-02-19 15:11:47' (length=19)
'updated_at' => string '2012-02-19 15:11:48' (length=19)
What I want to achieve now is to extract a simple associative array, where one "column" becomes the key and one "column" becomes the value. For the case id / value, the result should then look like that:
array
81 => 'foobar'
106 => 'barfoo'
I know that I could do nested loops to foreach through all of the arrays, but I was wondering if there is a quicker and more native method. I was playing around with array_intersect, but it does not seem to deliver what I need.
Well, this one doesn't involve nested loops:
$result = array();
foreach($queryResult as $row) {
$result[$row['id']] = $row['value'];
}
my array is setup as follow:
array
'testuri/abc' =>
array
'label' => string 'abc' (length=3)
'weight' => float 5
'testuri/abd' =>
array
'label' => string 'abd' (length=3)
'weight' => float 2
'testuri/dess' =>
array
'label' => string 'dess' (length=4)
'weight' => float 2
'testuri/gdm' =>
array
'label' => string 'gdm' (length=3)
'weight' => float 2
'testuri/abe' =>
array
'label' => string 'abe' (length=3)
'weight' => float 2
'testuri/esy' =>
array
'label' => string 'esy' (length=3)
'weight' => float 2
'testuri/rdx' =>
array
'label' => string 'rdx' (length=3)
'weight' => float 3
'testuri/tfc' =>
array
'label' => string 'tfc' (length=3)
'weight' => float 3
I want to get/filter the 5 elements with bigges 'weight'. Is there a php function to make this?
PS. My idea was to use foreach
Sort the array by the weight value in descending order and then get the first five values:
function cmpByWeight($a, $b) {
return $b['weight'] - $a['weight'];
}
uasort($array, 'cmpByWeight');
$firstFive = array_slice($array, 0, 5);
You'd be better using uasort with a callback that compares the 'weight' index of the passed values, and then array_slice to grab the first 5 elements (or last 5 depending on which way you sort...)
As far as I know there isn't.
You could use a heap for this, but for only 5 elements I'm not sure it's faster than just storing the top 5.
I would use array_multisort() and then grab the first 5 values.
array_multisort($weight, SORT_DESC, $label, SORT_ASC, $YOUR_ARRAY)
Then just grab $YOUR_ARRAY[0] - $YOUR_ARRAY[4] or iterate over the array to grab the first 5
[EDIT] here's a link to the function --> http://us3.php.net/manual/en/function.array-multisort.php
My English is not the best, i will try to explain, what i need. i can sort the array....but in the example above i have following:
1x weight 5
2x weight 3
5x weight 2
So...if I grab the first 5 elements, the another 3 with weight 2 will be ignored. So i need all 5 elements with weight 2....and so i have an array with 7 items.
Another example:
2x weight 5
4x weight 2
7x weight 1
All elements with weight1 must be ignored, So i get 6 elements in a new array..