PHP - Matching words in dynamic arrays - php

I've taken a look around but cant seem to find anything that does as needed.
Lets say I have 2 arrays in a function, however they are completely dynamic. So each time this function is run, the arrays are created based on a page that has been submitted.
I need to some how match these arrays and look for any phrase/words that appear in both.
Example: (with only a single element in each array)
Array 1: "This is some sample text that will display on the web"
Array 2: "You could always use some sample text for testing"
So in that example, the 2 arrays have a phrase that appears exactly the same in each: "Sample Text"
So seeing as these arrays are always dynamic I am unable to do anything like Regex because I will never know what words will be in the arrays.

You could find all words in an array of strings like this:
function find_words(array $arr)
{
return array_reduce($arr, function(&$result, $item) {
if (($words = str_word_count($item, 1))) {
return array_merge($result, $words);
}
}, array());
}
To use it, you run the end results through array_intersect:
$a = array('This is some sample text that', 'will display on the web');
$b = array('You could always use some sample text for testing');
$similar = array_intersect(find_words($a), find_words($b));
// ["some", "sample", "text"]

Array_intersect() should do this for you:
http://www.php.net/manual/en/function.array-intersect.php
*array_intersect() returns an array containing all the values of array1 that are present in all the arguments. Note that keys are preserved.*

maybe something like this:
foreach($arr as $v) {
$pos = strpos($v, "sample text");
if($pos !== false) {
// success
}
}
here is the manual:
http://de3.php.net/manual/de/function.strpos.php

Explode the two strings by spaces, and it is a simple case of comparing arrays.

Related

How to change order of substrings inside a larger string?

This is fairly confusing, but I'll try to explain as best I can...
I've got a MYSQL table full of strings like this:
{3}12{2}3{5}52
{3}7{2}44
{3}15{2}2{4}132{5}52{6}22
{3}15{2}3{4}168{5}52
Each string is a combination of product options and option values. The numbers inside the { } are the option, for example {3} = Color. The number immediately following each { } number is that option's value, for example 12 = Blue. I've already got the PHP code that knows how to parse these strings and deliver the information correctly, with one exception: For reasons that are probably too convoluted to get into here, the order of the options needs to be 3,4,2,5,6. (To try to modify the rest of the system to accept the current order would be too monumental a task.) It's fine if a particular combination doesn't have all five options, for instance "{3}7{2}44" delivers the expected result. The problem is just with combinations that include option 2 AND option 4-- their order needs to be switched so that any combination that includes both options 2 and 4, the {4} and its corresponding value comes before the {2} and it's corresponding value.
I've tried bringing the column into Excel and using Text to Columns, splitting them up by the "{" and "}" characters and re-ordering the columns, but since not every string yields the same number of columns, the order gets messed up in other ways (like option 5 coming before option 2).
I've also experimented with using PHP to explode each string into an array (which I thought I could then re-sort) using "}" as the delimiter, but I had no luck with that either because then the numbers blend together in other ways that make them unusable.
TL;DR: I have a bunch of strings like the ones quoted above. In every string that contains both a "{2}" and a "{4}", the placement of both of those values needs to be switched, so that the {4} and the number that follows it comes before the {2} and the number that follows it. In other words:
{3}15{2}3{4}168{5}52
needs to become
{3}15{4}168{2}3{5}52
The closest I've been able to come to a solution, in pseudocode, would be something like:
for each string,
if "{4}" is present in this string AND "{2}" is present in this string,
take the "{4}" and every digit that follows it UNTIL you hit another "{" and store that substring as a variable, then remove it from the string.
then, insert that substring back into the string, at a position starting immediately before the "{2}".
I hope that makes some kind of sense...
Is there any way with PHP, Excel, Notepad++, regular expressions, etc., that I can do this? Any help would be insanely appreciated.
EDITED TO ADD: After several people posted solutions, which I tried, I realized that it would be crucial to mention that my host is running PHP 5.2.17, which doesn't seem to allow for usort with custom sorting. If I could upvote everyone's solution (all of which I tried in PHP Sandbox and all of which worked), I would, but my rep is too low.
How would something like this work for you. The first 9 lines just transform your string into an array with each element being an array of the option number and value. The Order establishes an order for the items to appear in and the last does a usort utilizing the order array for positions.
$str = "{3}15{2}2{4}132{5}52{6}22";
$matches = array();
preg_match_all('/\{([0-9]+)\}([0-9]+)/', $str, $matches);
array_shift($matches);
$options = array();
for($x = 0; $x < count($matches[0]); $x++){
$options[] = array($matches[0][$x], $matches[1][$x]);
}
$order = [3,4,2,5,6];
usort($options, function($a, $b) use ($order) {
return array_search($a[0], $order) - array_search($b[0], $order);
});
To get you data back into the required format you would just
$str = "";
foreach($options as $opt){
$str.="{".$opt[0]."}".$opt[1];
}
On of the bonuses here is that when you add a new options type inserting adjusting the order is just a matter of inserting the option number in the correct position of the $order array.
First of all, those options should probably be in a separate table. You're breaking all kinds of normalization rules stuffing those things into a string like that.
But if you really want to parse that out in php, split the string into a key=>value array with something like this:
$options = [];
$pairs = explode('{', $option_string);
foreach($pairs as $pair) {
list($key,$value) = explode('}', $pair);
$options[$key] = $value;
}
I think this will give you:
$options[3]=15;
$options[2]=3;
$options[4]=168;
$options[5]=52;
Another option would be to use some sort of existing serialization (either serialize() or json_encode() in php) instead of rolling your own:
$options_string = json_encode($options);
// store $options_string in db
then
// get $options_string from db
$options = json_decode($options_string);
Here's a neat solution:
$order = array(3, 4, 2, 5, 6);
$string = '{3}15{2}3{4}168{5}52';
$split = preg_split('#\b(?={)#', $string);
usort($split, function($a, $b) use ($order) {
$a = array_search(preg_replace('#^{(\d+)}\d+$#', '$1', $a), $order);
$b = array_search(preg_replace('#^{(\d+)}\d+$#', '$1', $b), $order);
return $a - $b;
});
$split = implode('', $split);
var_dump($split);

String Combinations Matching

Suppose a string:
$str = 'a_b_c';
I want match all possible combination with a, b, c with above. For example:
b_a_c, c_a_b, a_c_b..etc will be give true when compare with above $str.
NOTE:
$str may be random. eg: a_b, k_l_m_n etc
I would split your string into an array, and then compare it to an array of elements to match on.
$originalList = explode('_', 'a_b_c');
$matchList = array('a', 'b', 'c');
$diff = array_diff($matchList, $originalList);
if (!empty($diff)) {
// At least one of the elements in $matchList is not in $originalList
}
Beware of duplicate elements and what not, depending on how your data comes in.
Documentation:
array_diff()
explode()
There is no builtin way to quickly do this. Your task can be accomplished many different ways which will vary on how general they are. You make no mention of null values or checking the formatting of the string, so something like this might work for your purpose:
function all_combos($str,$vals) {
$s=explode("_",$str);
foreach($s as $c) {
if(!in_array($s,$vals)) return false;
}
return true;
}
Call like all_combos("b_c_a",array("a","b","c"));

Compare All strings in a array to all strings in another array, PHP

What i am trying to do is really but i am going into a lot of detail to make sure it is easily understandable.
I have a array that has a few strings in it. I then have another that has few other short strings in it usually one or two words.
I need it so that if my app finds one of the string words in the second array, in one of the first arrays string it will proceed to the next action.
So for example if one of the strings in the first array is "This is PHP Code" and then one of the strings in the second is "PHP" Then it finds a match it proceeds to the next action. I can do this using this code:
for ( $i = 0; $i < count($Array); $i++) {
$Arrays = strpos($Array[$i],$SecondArray[$i]);
if ($Arrays === false) {
echo 'Not Found Array String';
}
else {
echo 'Found Array String';
However this only compares the First Array object at the current index in the loop with the Second Array objects current index in the loop.
I need it to compare all the values in the array, so that it searches every value in the first array for the First Value in the second array, then every value in the First array for the Second value in the second array and so on.
I think i have to do two loops? I tried this but had problems with the array only returning the first value.
If anyone could help it would be appreciated!
Ill mark the correct answer and + 1 any helpful comments!
Thanks!
Maybe the following is a solution:
// loop through array1
foreach($array1 as $line) {
// check if the word is found
$word_found = false;
// explode on every word
$words = explode(" ", $line);
// loop through every word
foreach($words as $word) {
if(in_array($word, $array2)) {
$word_found = true;
break;
}
}
// if the word is found do something
if($word_found) {
echo "There is a match found.";
} else {
echo "No match found."
}
}
Should give you the result you want. I'm absolute sure there is a more efficient way to do this.. but thats for you 2 find out i quess.. good luck
You can first normalize your data and then use PHP's build in array functions to get the intersection between two arrays.
First of all convert each array with those multiple string with multiple words in there into an array only containing all words.
A helpful function to get all words from a string can be str_word_count.
Then compare those two "all words" arrays with each other using array_intersect.
Something like this:
$words1 = array_unique(str_word_count(implode(' ', $Array), 1));
$words2 = array_unique(str_word_count(implode(' ', $SecondArray), 1));
$intersection = array_intersect($words1, $words2);
if(count($intersection))
{
# there is a match!
}
function findUnit($packaging_units, $packaging)
{
foreach ($packaging_units as $packaging_unit) {
if (str_contains(strtoupper($packaging[3]), $packaging_unit)) {
return $packaging_unit;
}
}
}
Here First parameter is array and second one is variable to find

how to search an array in php?

suppose I have an array of names, what I want is that I want to search this particular array against the string or regular expression and then store the found matches in another array. Is this possible ? if yes then please can your give me hint ? I am new to programming.
To offer yet another solution, I would recommend using PHP's internal array_filter to perform the search.
function applyFilter($element){
// test the element and see if it's a match to
// what you're looking for
}
$matches = array_filter($myArray,'applyFilter');
As of PHP 5.3, you can use an anonymous function (same code as above, just declared differently):
$matches = array_filter($myArray, function($element) {
// test the element and see if it's a match to
// what you're looking for
});
what you would need to di is map the array with a callback like so:
array_filter($myarray,"CheckMatches");
function CheckMatches($key,$val)
{
if(preg_match("...",$val,$match))
{
return $match[2];
}
}
This will run the callback for every element in the array!
Updated to array_filter
well in this case you would probably do something along the lines of a foreach loop to iterate through the array to find what you are looking for.
foreach ($array as $value) {
if ($searching_for === $value) {/* You've found what you were looking for, good job! */}
}
If you wish to use a PHP built in method, you can use in_array
$array = array("1", "2", "3");
if (in_array("2", $array)) echo 'Found ya!';
1) Store the strings in array1
2) array2 against you want to match
3) array3 in which you store the matches
$array1 = array("1","6","3");
$array2 = array("1","2","3","4","5","6","7");
foreach($array1 as $key=>$value){
if(in_array($value,$array2))
$array3[] = $value;
}
echo '<pre>';
print_r($array3);
echo '</pre>';

How to find a string in an array in PHP?

I have an array:
$array = array("apple", "banana", "cap", "dog", etc..) up to 80 values.
and a string variable:
$str = "abc";
If I want to check whether this string ($str) exists in the array or not, I use the preg_match function, which is like this:
$isExists = preg_match("/$str/", $array);
if ($isExists) {
echo "It exists";
} else {
echo "It does not exist";
}
Is it the correct way? If the array grows bigger, will it be very slow? Is there any other method? I am trying to scaling down my database traffic.
And if I have two or more strings to compare, how can I do that?
bool in_array ( mixed $needle , array $haystack [, bool $strict ] )
http://php.net/manual/en/function.in-array.php
If you just need an exact match, use in_array($str, $array) - it will be faster.
Another approach would be to use an associative array with your strings as the key, which should be logarithmically faster. Doubt you'll see a huge difference between that and the linear search approach with just 80 elements though.
If you do need a pattern match, then you'll need to loop over the array elements to use preg_match.
You edited the question to ask "what if you want to check for several strings?" - you'll need to loop over those strings, but you can stop as soon as you don't get a match...
$find=array("foo", "bar");
$found=count($find)>0; //ensure found is initialised as false when no terms
foreach($find as $term)
{
if(!in_array($term, $array))
{
$found=false;
break;
}
}
preg_match expects a string input not an array. If you use the method you described you will receive:
Warning: preg_match() expects parameter 2 to be string, array given in LOCATION on line X
You want in_array:
if ( in_array ( $str , $array ) ) {
echo 'It exists';
} else {
echo 'Does not exist';
}
Why not use the built-in function in_array? (http://www.php.net/in_array)
preg_match will only work when looking for a substring in another string. (source)
If you have more than one value you could either test every value separatly:
if (in_array($str1, $array) && in_array($str2, $array) && in_array($str3, $array) /* … */) {
// every string is element of the array
// replace AND operator (`&&`) by OR operator (`||`) to check
// if at least one of the strings is element of the array
}
Or you could do an intersection of both the strings and the array:
$strings = array($str1, $str2, $str3, /* … */);
if (count(array_intersect($strings, $array)) == count($strings)) {
// every string is element of the array
// remove "== count($strings)" to check if at least one of the strings is element
// of the array
}
The function in_array() only detects complete entries if an array element. If you wish to detect a partial string within an array, each element must be inspected.
foreach ($array AS $this_string) {
if (preg_match("/(!)/", $this_string)) {
echo "It exists";
}
}

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