    $percentage = 50;
    $totalWidth = 350;

    $new_width = ($percentage / 100) * $totalWidth;


Divide `$percentage` by 100 and multiply to `$totalWidth`. Simple maths.

PHP does not allow

    class Foo
    {
        private const my_private_const;

but of course allows

    const my_const;

So in effect constants are global because I can access `my_const` anywhere using `Foo::my_const`

Is there a way to make private constants?


Are private constants possible in PHP?

I need to create a new MySQL user with limited permission on an existing Amazon RDS instance.  After encountering a couple error messages I was sort of able to do this using the official MySQL Administrator tool and the user now appears in the list.  However, I&#39;m unable to assign any schema privileges as all the users are greyed out.  I&#39;m logged in as the &quot;master user&quot; created when the instance was launched.  Not sure where to go from here.  I do have the RDS command line tools installed but wasn&#39;t able to track down anything there either. Ideas

Creating A New MySQL User In Amazon RDS Environment

I would like to calculate, in PHP, the percentage of a number. For example:

    $percentage = 50;
    $totalWidth = 350;
    
For this example, 50% of 350 = 175

How can I do that?

How do I calculate the percentage of a number?

I would like to calculate, in PHP, the percentage of a number. For example:
<pre><code class="hljs language-ini">$percentage = 50;
$totalWidth = 350;
</code></pre>
For this example, 50% of 350 = 175
How can I do that?

I&#39;m calling `json_encode()` on data that comes from a MySQL database with `utf8_general_ci` collation. The problem is that some rows have weird data which I can&#39;t clean. For example symbol `�`, so once it reaches `json_encode()`, it fails with `json_encode(): Invalid UTF-8 sequence in argument`.

I&#39;ve tried `utf8_encode()` and `utf8_decode()`, even with `mb_check_encoding()` but it keeps getting through and causing havoc. 

Running PHP 5.3.10 on Mac. So the question is - how can I clean up invalid utf8 symbols, keeping the rest of data, so that `json_encoding()` would work?


Update. Here is a way to reproduce it:

    echo json_encode(pack(&quot;H*&quot; ,&#39;c32e&#39;));

json_encode(): Invalid UTF-8 sequence in argument

I&#39;m need to check if `memory_limit` is at least `64M` in my script installer. This is just part of PHP code that should work, but probably due to this &quot;M&quot; it&#39;s not reading properly the value. How to fix this ?

      //memory_limit
        echo &quot;&lt;phpmem&gt;&quot;;
        if(key_exists(&#39;PHP Core&#39;, $phpinfo))
        {
            if(key_exists(&#39;memory_limit&#39;, $phpinfo[&#39;PHP Core&#39;]))
            {
                $t=explode(&quot;.&quot;, $phpinfo[&#39;PHP Core&#39;][&#39;memory_limit&#39;]);
                if($t[0]&gt;=64)
                    $ok=1;
                else
                    $ok=0;
                echo &quot;&lt;val&gt;{$phpinfo[&#39;PHP Core&#39;][&#39;memory_limit&#39;]}&lt;/val&gt;&lt;ok&gt;$ok&lt;/ok&gt;&quot;;
            }
            else
               echo &quot;&lt;val&gt;&lt;/val&gt;&lt;ok&gt;0&lt;/ok&gt;&quot;;
        }
        else
            echo &quot;&lt;val&gt;&lt;/val&gt;&lt;ok&gt;0&lt;/ok&gt;&quot;;
        echo &quot;&lt;/phpmem&gt;\n&quot;; 

checking memory_limit in PHP

I have a table with string values in the format of **Friday 20th April 2012** in a field called `Film_Release`

I am looping through and I want to convert them in `datetime` and roll them out into another table. My second table has a column called `Films_Date`, with a format of `DATE`. I am receiving this error

&gt; Object of class DateTime could not be converted to string

    $dateFromDB = $info[&#39;Film_Release&#39;];
    $newDate = DateTime::createFromFormat(&quot;l dS F Y&quot;,$dateFromDB); //( http:php.net/manual/en/datetime.createfromformat.php)

Then I insert `$newdate` into the table through an insert command.

Why am I be getting such an error?

Object of class DateTime could not be converted to string

I&#39;m pulling JSON from Instagram:

`$instagrams = json_decode($response)-&gt;data;`

Then parsing variables into a PHP array to restructure the data, then re-encoding and caching the file:

`file_put_contents($cache,json_encode($results));`

When I open the cache file all my forward slashes &quot;/&quot; are being escaped:

`http:\/\/distilleryimage4.instagram.com\/410e7...`

I gather from my searches that `json_encode()` automatically does this...is there a way to disable it?

json_encode() escaping forward slashes

  I dont understand when I echo $httpCode I always get 0, I was expecting 404 when I change $html_brand into a broken url. Is there anything that I miss or do not know of? Thanks.

     //check if url exist
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $html_brand);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
    $response = curl_exec($ch); 
    $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    
    if ($httpCode == 404) {
        echo &quot;The Web Page Cannot Be Found&quot;;
        return;
    }
    curl_close($ch);

PHP cURL HTTP CODE return 0

Translating an elements Y axis 50% will move it down 50% of its own height, not 50% of the parents height as I would expect. How do I tell a translating element to base it&#39;s translation percentage on the parent element? Or am I not understanding something?

http://jsfiddle.net/4wqEm/2/

Translate X and Y percentage values based on elements height and width?

Consider the four percentages below, represented as `float` numbers:

        13.626332%
        47.989636%
         9.596008%
        28.788024%
       -----------
       100.000000%

I need to represent these percentages as whole numbers. If I simply use `Math.round()`, I end up with a total of 101%. 


    14 + 48 + 10 + 29 = 101

If I use `parseInt()`, I end up with a total of 97%. 


    13 + 47 + 9 + 28 = 97

What&#39;s a good algorithm to represent any number of  percentages as whole numbers while still maintaining a total of 100%?

---
**Edit**: After reading some of the comments and answers, there are clearly many ways to go about solving this.

In my mind, to remain true to the numbers, the &quot;right&quot; result is the one that minimizes the overall error, defined by how much error rounding would introduce relative to the actual value:

            value  rounded     error               decision
       ----------------------------------------------------
        13.626332       14      2.7%          round up (14)
        47.989636       48      0.0%          round up (48)
         9.596008       10      4.0%    don&#39;t round up  (9)
        28.788024       29      2.7%          round up (29)

In case of a tie (3.33, 3.33, 3.33) an arbitrary decision can be made (e.g. 3, 4, 3).

How to make rounded percentages add up to 100%

I&#39;m having troubles with a flexbox column in that children of the flex&#39;d element don&#39;t respond to `height` in percentages. I&#39;ve only checked this in Chrome, and from what I understand it&#39;s a Chrome only problem. Here&#39;s my example:

HTML

    &lt;div class=&#39;flexbox&#39;&gt;
      &lt;div class=&#39;flex&#39;&gt;
        &lt;div class=&#39;flex-child&#39;&gt;&lt;/div&gt;
      &lt;/div&gt;
      &lt;div class=&#39;static&#39;&gt;&lt;/div&gt;
    &lt;/div&gt;

CSS

    .flexbox{
      position:absolute;
      background:black;
      width:100%;
      height:100%;
      
      display: flex;
      flex-direction:column;
    }
    
    .flex{
      background:blue;
      flex:1;
    }
    
    .flex-child{
      background:red;
      height:100%;
      width:100%;
      display:block;
    }
    
    .static{
      background:green;
      width:100%;
      height:5rem;
    }

[Here&#39;s the CodePen.](http://codepen.io/CourtDemone/pen/acLBG)

I want it so the red `.flex-child` fills the blue `.flex`. Why doesn&#39;t `height:100%` work?

Height 100% on flexbox column child

I am trying to simply format a number as a percent with two decimal places. If it is 37 divided by 38 (aka .973684210526315789), I would like it to show 97.36 % in the SQL output. I know it is recommended to do formatting in the Application, however this is for an automated export. This is using SQL Server 2008.

Here is what I have now:

    select CONVERT(VARCHAR(50),cast(37 as decimal)/cast(38 as decimal)*100)+&#39; %&#39; AS [%]

If you could explain what the various parameters are as well in any function that would be helpful.

Format number as percent in MS SQL Server

I want to get a percentage of a particular value in a df column. Say I have a df with (col1, col2 , col3, gender)  gender column has values of M, F, or Other. I want to get the percentage of M, F, Other values in the df. 

I have tried this, which gives me the number M, F, Other instances, but I want these as a percentage of the total number of values in the df.

    df.groupby(&#39;gender&#39;).size()

Can someone help?

Content Type	Original Author	Original Content on Stackoverflow
Question	John Smeuth	View Question on Stackoverflow
Solution 1 - Php	pogeybait	View Answer on Stackoverflow
Solution 2 - Php	hkf	View Answer on Stackoverflow

How do I calculate the percentage of a number?

Php Problem Overview

Php Solutions

Solution 1 - Php

Solution 2 - Php

Creating A New MySQL User In Amazon RDS Environment

Are private constants possible in PHP?

Attributions