Calculating Average (Mean) in PHP - php

I'm a bit of a beginner with PHP and am implementing a review aggregator system for a few products.
I have created the input fields and am outputting the results from these fields using this code:
{ echo '<div class="review1">Review 1: '; the_field('review1'); '</div>';}
{ echo '<div class="review2">Review 2: '; the_field('review2'); '</div>';}
{ echo '<div class="review3">Review 3: '; the_field('review3'); '</div>';}
{ echo '<div class="review4">Review 4: '; the_field('review4'); '</div>';}
{ echo '<div class="review5">Review 5: '; the_field('review5'); '</div>';}
I want to use PHP to calculate the average (mean) however the number I am using to calculate this is set to 5 as that is the total number of number fields I have. Here is the code I am using
{ echo (get_field('review1')+get_field('review2')+get_field('review3')+get_field('review4')+get_field('review5'))/5;}
The problem with this method is that sometimes the fields will not contain a value so the number to divide by would need to be 1, 2, 3 or 4 instead of 5 depending on the total number of review fields that have a value.
Essentially I need to replace "/5" with "/n" where "n" is the total number of fields with values.
Can anyone please assist?
Regards,
Peter

I would put the values into an array, then filter out non-numeric values, and then do the calculation of the average:
$array = [ 123, 45, null, 17, 236 ];
// $array = [ get_field('review1'), get_field('review2'), etc. ]
$values = array_filter($array, 'is_numeric');
$result = array_sum($values) / count($values);
echo $result; // Output: 105.25

$items = ['1','2','7','',''];
$average = calculateAverage($items);
echo $average;
function calculateAverage($items)
{
$total = 0;
$count = 0;
foreach($items as $item)
{
if(is_numeric($item))
{
$total += $item;
$count++;
}
}
return $total / $count;
}
If the number is empty, it will not add the number to the devider

Related

How to count total entries in an array, and display the sum total in PHP

I have some code that processes an array of values, each one with a value 1 or 0.
<?php
$GD_album = [
[$gdclock,1],
[$gdheart,1],
[$gdblue,1],
[$gdblack5th,0],
[$gdgreymarble,1],
[$gdblack7th,0]
];
$GD[have] = '';
foreach($GD_album as list($name, $own)) {if ($own === 1)echo $name;}
echo $GD[have];
?>
Each of my $gd*** variables draws a block of PHP and HTML code, and the foreach I have above will only draw the ones with a "1", and skip the ones with a 0. This works great.
What I'd like to do is have a piece of code that will add up each variable with a value of 1; for a total of 4. I'd also like some code to add up 0; for a total of 2. Then I would like to add those two results together for a total of 6.
I have tried the count() and array_sum() functions with little success. What I tried that gave me some results is:
<?php
$GD[h_total] = '';
foreach($GD_album as list($name, $own))
{if ($own === 1) echo count($own);}
echo $GD[h_total];
?>
<?php
$GD[w_total] = '';
foreach($GD_album as list($name, $own))
{if ($own === 0) echo count($own);}
echo $GD[w_total];
?>
This however, only outputs: "1111" and not "4". And "00", not "2", respectively. Ideally, some code that could count my 0's & 1's, also add them, and stylize as "Have 4/6" or "Need 2/6" would be best! Can anyone point me in the right direction? Thanks!
Try the code below:
<?php
$GD_album = [
['gdclock',1],
['gdheart',1],
['gdblue',1],
['gdblack5th',0],
['gdgreymarble',1],
['gdblack7th',0]
];
$GD['h_total'] = [];
foreach($GD_album as list($name, $own)){
if(isset($GD['h_total'][$own])){
$GD['h_total'][$own]++;
}else{
$GD['h_total'][$own] = 1;
}
}
echo 'total zeros: '. $GD['h_total'][0];
echo 'total ones: '. $GD['h_total'][1];
echo 'total: ' .array_sum($GD['h_total']);
The output:
total zeros: 2
total ones: 4
total: 6

Optimizing Find nearest sum of numbers in array to a given number

Say I have an array [10000,5000,1000,1000] and I would like to find the closest sum of numbers to a given number. Sorry for the bad explanation but here's an example:
Say I have an array [10000,5000,1000,1000] I want to find the closest numbers to, say 6000.
Then the method should return 5000 and 1000
another example : we want the closest to 14000 , so then he should return 10000 and 5000
I've tried with code below, here is working one but if the $desiredSum and $numbers array is big. it's running so slow until php execution timeout
$numbers = array(
10000,5000,1000,1000
);
$desiredSum = 6000;
$minDist = null;
$minDist_I = null;
// Iterate on every possible combination
$maxI = pow(2,sizeof($numbers));
for($i=0;$i<$maxI;$i++) {
if(!(($i+1) % 1000)) echo ".";
// Figure out which numbers to select in this
$sum = 0;
for($j=0;$j<sizeof($numbers);$j++) {
if($i & (1 << $j)) {
$sum += $numbers[$j];
}
}
$diff = abs($sum - $desiredSum);
if($minDist_I === null || $diff < $minDist) {
$minDist_I = $i;
$minDist = $diff;
}
if($diff == 0) break;
}
$chosen = array();
for($j=0;$j<sizeof($numbers);$j++) {
if($minDist_I & (1 << $j)) $chosen[] = $numbers[$j];
}
echo "\nThese numbers sum to " . array_sum($chosen) . " (closest to $desiredSum): ";
echo implode(", ", $chosen);
echo "\n";
Anyone can help me out ?
<?php
function coinChange($numbers,$desiredSum){
sort($numbers);
$set = [];
$set[0] = [];
for($i = $numbers[0];$i <= $desiredSum;++$i){
foreach($numbers as $index => $current_number){
if($i >= $current_number && isset($set[$i - $current_number])){
if(isset($set[$i - $current_number][$index])) continue;
$set[$i] = $set[$i - $current_number];
$set[$i][$index] = true;
break;
}
}
}
if(count($set) === 0){
return [0,[]];
}
if(isset($set[$desiredSum])){
return [
$desiredSum,
formatResult($numbers,array_keys($set[$desiredSum]))
];
}else{
$keys = array_keys($set);
$nearestSum = end($keys);
$sum = 0;
$rev_numbers = array_reverse($numbers);
$result = [];
foreach($rev_numbers as $number){
$sum += $number;
$result[] = $number;
if($sum > $nearestSum && abs($nearestSum - $desiredSum) > abs($sum - $desiredSum)){
$nearestSum = $sum;
break;
}else if($sum > $nearestSum && abs($nearestSum - $desiredSum) < abs($sum - $desiredSum)){
$result = formatResult($numbers,array_keys($set[$nearestSum]));
break;
}
}
return [
$nearestSum,
$result
];
}
}
function formatResult($numbers,$keys){
$result = [];
foreach($keys as $key) $result[] = $numbers[$key];
return $result;
}
print_r(coinChange([10000,5000,1000,1000],14000));
print_r(coinChange([10000,5000,1000,1000],13000));
print_r(coinChange([100000,100000,100000,100000,100000,100000,50000,50000,50000,50000,10000,10000,500,500,500,1000,1000],250000));
print_r(coinChange([100000,100000,100000,100000,100000,100000,50000,50000,50000,50000,10000,10000,500,500,500,1000,1000],179999));
Demo: https://3v4l.org/hBGeW
Algorithm:
This is similar to coin change problem.
We first sort the numbers.
Now, we iterate from minimum number in the array to the desired sum.
Inside it, we iterate through all elements in the array.
Now, we can make $i(which is a sum) only if we have made sum $i - $current_number. If we have the previous one, then we add $current_number to our collection for sum $i.
Two Scenarios:
If we can make the exact sum, then we return the result as is.
If we can't, then are 2 possibilities:
We would already have nearest sum possible in our $set which would be the last entry. We keep them in a variable.
Now, the nearest sum could also be higher than the desired sum. So, we get the larger sum and check if it's nearer than nearest smallest sum and then compare both and return the result.
Result format:
Let's take the below sample output:
Array
(
[0] => 15000
[1] => Array
(
[0] => 10000
[1] => 5000
)
)
It simply means that the first index is the nearest sum possible and array at 2nd index is all elements it took from $numbers to make that sum.

Php foreach split list into columns (preferably equally)

I have an ordered list which is 19 entries long (but could change and be more or less). I'm listing it on a drop down menu but because of its length the column is dropping below the fold of the page.
I'd like to create a separate column (ul or div) to either divide the list into 2 or 3 equally, or have set list sizes e.g. max 7 per list.
Any ideas? Current code:
<div id="colour" class="dropmenudiv">
<?php
$sql = "select * from rug_colours where id <> 0 and active = 1 order by name";
$rs = $database->query($sql);
$index = 0;
foreach($rs as $v) {
echo "<a href=\"//$base_url/?action=search&colour=".$v['id']."\" >".$v['name']."</a>";
}
?>
Try something along the lines of:
<div id="colour" class="dropmenudiv">
<?php
$sql = "select * from rug_colours where id <> 0 and active = 1 order by name";
$rs = $database->query($sql);
$column_height = 7;
echo "<div class='column'>";
foreach($rs as $idx => $v) {
echo "<a href=\"//$base_url/?action=search&colour=".$v['id']."\" >".$v['name']."</a>";
if($idx % $column_height) echo "</div><div class='column'>";
}
echo "</div>";
?>
and for equal split you might try this:
$max_column_height = 7;
$no_of_cols = ceil(count($rs) / $max_column_height);
$column_height = floor($count($rs) / $no_of_cols);
You should use index variable to divide it into 2 or 3 div.
Following is example to make it in three parts:
$index = 0;
foreach($rs as $v) {
if($index > 7){
$index = 0; // reset to zero. You can also seperate it by any tag div or ul if you want
}
echo "<a href=\"//$base_url/?action=search&colour=".$v['id']."\" >".$v['name']."</a>";
$index++;
}
For an evenly spread distribution, first divide the number of elements by 7 (or whichever maximum rows you want to allow), rounding upwards. This gives the number of columns. Then divide the number of elements by the number of columns, rounding upwards: this gives you the actual number of rows you need.
I like array_chunk for this purpose:
$maxRowCount = 7;
$colCount = ceil(count($rs) / $maxRowCount);
$chunkSize = ceil(count($rs) / $colCount);
foreach(array_chunk($rs, $chunkSize) as $column) {
echo "<div class='column'>\n";
foreach($column as $v) {
echo "<a href=\"//$base_url/?action=search&colour={$v['id']}\" >{$v['name']}</a>";
}
echo "</div>\n";
}
You can create array of columns based on current index in foreach() loop like
$abc = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15];
$cols = [];
$perCol = 7;
foreach($abc as $index => $val) {
$colInd = $index / $perCol;
$cols[$colInd][] = $val;
}
print_r($cols);
This will split data in $abc into 3 coluns by 7 items per column.

Division with php

Im trying to get out an average value from a vote function.
<?php
$file = file("textfile.txt");
$textfil = file_get_contents("textfile.txt");
$textfill = str_split($textfil);
echo "Number of votes: " . count($textfill) . "<br>";
$sum = 0;
foreach ($textfill as $vote) {
$sum = $sum + intval($vote);
}
echo "Average: " . $sum;
?>
Simple by substitute (+) with a (/), and even tried a (%). But still getting error message.
Would appreciate alot if anyone could help me out and tell me what im doing wrong.
/thanks
Edit
Sidenote: Please read an explanation under "First answer given" further down below.
This version will take into account any blank lines in a file, if the content looks like:
1
2
3
// <- blank line
Sidenote: Please provide a sample of your text file. A comment has already been given to that effect.
PHP
<?php
// first line not required
// $file = file("textfile.txt");
$textfil = file_get_contents("textfile.txt");
$textfill = array_filter(array_map("trim", file("textfile.txt")), "strlen");
echo "Number of votes: " . count($textfill) . "<br>";
$sum = 0;
foreach ($textfill as $vote) {
$sum += intval($vote);
}
$avg = $sum / count($textfill);
echo "Average: " . $avg;
?>
First answer given
Using the following in a text file: (since no example of file content was given)
5
5
5
IMPORTANT NOTE: There should not be a carriage return after the last entry.
produced
Number of votes: 5
Average: 3
which is false, since there are 3 entries in the text file.
explode() should be used, and not str_split()
The following using the same text file produced:
Number of votes: 3
Average: 5
which is correct. In simple mathematics, averages are done by adding all numbers then dividing them by how many numbers there are.
In this case it's 3 numbers (all 5's) added equals 15, divided by 3 is 5.
Sidenote: The first line is not required $file = file("textfile2.txt");
<?php
// first line not required
// $file = file("textfile.txt");
$textfil = file_get_contents("textfile.txt");
$textfill = explode("\n", $textfil);
echo "Number of votes: " . count($textfill) . "<br>";
$sum = 0;
foreach ($textfill as $vote) {
$sum += intval($vote);
}
$avg = $sum / count($textfill);
echo "Average: " . $avg;
?>
Footnotes:
If the average comes out to 8.33333 and you would like it to be rounded off to 8, use:
echo "Average: " . floor($avg);
If the average comes out to 8.33333 and would like it to be as 9 you would use:
echo "Average: " . ceil($avg);
ceil() function
floor() function
You may be mixing in stuff that can't be divided, like text, etc. I don't know what your text file looks like. intval may be having a problem with arrays. You may try:
foreach ($textfill as $vote) {
if(is_int($vote) {
$sum += $vote;
}
}
echo "Average: " . $sum;
Lower school math says:
foreach ($textfill as $vote) {
$sum += intval($vote);
}
$avg = $sum / count($textfill);
The average value is calculated by divide the sum with the number of votes. This line will print the average value:
echo "Average: " . $sum/count($textfill);

stuck here with lotto grid

I have a grid with 42 nrs where I will use the rand() function to pick out numbers from the grid and and mark them
so far I came up with
<?php
$row="";
print ("<table border=\"1\">");
for ($i=0; $i<6; $i++)
{
print ("<tr>");
for ($j=0; $j<7; $j++)
{
$random = rand(1,42);
$row += "(string)$random";
$som = $som + 1;
print("<th>".$som);
}
("</tr>");
}
print ("</table>");
print ("$rij");
// here I'm just testing to see if I can get a list of random numbers
for ($i=0; $i<6; $i++){
$randomNr = rand(1,42);
echo "$randomNr<br/>";
}
?>
I guess the idea is to match the numbers out of the rand function to the indexes of the table. But i'm really stuck here at getting the table to convert to an arra so I can match the index with the random numbers.
You're probably not too far off with your own attempt. You would just need to generate 6 random unique numbers and compare against them. Easiest way to do that is to generate an array using range() and pick the random numbers with array_rand() (which actually returns indexes, so you need a bit of additional code to get the values). Then you just need to find whether the currently outputted number is in the chosen number array using in_array()
Here's an example function of the general case that expands Sondre's example a bit. The function in the example takes following arguments: Total random numbers picked, Smallest number in the grid, Biggest number in the grid and the numbers per row in the grid. The function returns the generated HTML table source a string.
<?php
function generateHighlightedLotteryTable ($count = 6, $min = 1, $max = 42, $perRow = 7)
{
// Generate the picked numbers (actually we just get their indexes)
$nums = array_rand(range($min, $max), $count);
$output = "<table>\n";
for ($n = $min; $n <= $max; $n++)
{
// get "index" of the number, i.e. $min is the first number and thus 0
$i = $n - $min;
if ($i % $perRow == 0)
{
$output .= "<tr>";
}
// If the current number is picked
if (in_array($i, $nums))
{
$output .= "<td><strong>$n</strong></td>";
}
// If the current number hasn't been chosen
else
{
$output .= "<td>$n</td>";
}
if ($i % $perRow == $perRow - 1)
{
$output .= "</tr>\n";
}
}
// End row, if the numbers don't divide evenly among rows
if (($n - $min) % $perRow != 0)
{
$output .= "</tr>\n";
}
$output .= "</table>";
return $output;
}
echo generateHighlightedLotteryTable();
?>
I hope this is what you were trying to achieve.
This would create a grid of 42 numbers and mark out a random one. If you want to mark out more create and array and check against that insted of just the rand variable. In you're original code there you were actually running the rand-function 42 times which I guess is unintended.
EDIT: Or did you need the grid to be filled with random numbers?
$rand = rand(1, 42);
echo "<table>";
for($i = 1;$i <= 42; $i++) {
if($i%7 == 1) {
echo "<tr>";
}
$print = $rand == $i ? "<strong>" . $i . "</strong>" : $i;
echo "<td>" . $print . "</td>";
if($i%7 == 0) {
echo "</tr>";
}
}
echo "</table>";

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