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What is the difference between Reader and InputStream?
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An InputStream is the raw method of getting information from a resource. It grabs the data byte by byte without performing any kind of translation. If you are reading image data, or any binary file, this is the stream to use.
A Reader is designed for character streams. If the ...
Use email address as primary key?
...nt comparison. However, this does not matter if you simply retrieve a user from the database using the e-mail address. It does matter if you have complex queries with multiple joins.
If you store information about users in multiple tables, the foreign keys to the users table will be the e-mail addr...
What is output buffering?
...rld'; // save to output buffer
$output = ob_get_clean(); // Get content from the output buffer, and discard the output buffer ...
$output = strtoupper($output); // manipulate the output
echo $output; // send to output stream / Browser
// OUTPUT:
HELLO WORLD
Examples: Hackingwithphp.com
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What is the difference between and ?
...e page.
<div>, on the other hand, does not convey any meaning, aside from any found in its class, lang and title attributes.
So no: using a <div> does not define a section in HTML.
From the spec:
<section>
The <section> element represents a generic section of a document or a...
Clearing using jQuery
...you must call .preventDefault() on the event to prevent the <button> from triggering a submit.
EDIT
Does not work in IE 11 due to an unfixed bug. The text (file name) is cleared on the input, but its File list remains populated.
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Unsigned keyword in C++
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From the link above:
Several of these types can be modified using the keywords signed, unsigned, short, and long. When one of these type modifiers is used by itself, a data type of int is assumed
This means that you can...
How do I debug an MPI program?
...ce Analysis Tool (STAT). We use this at Livermore to collect stack traces from potentially hundreds of thousands of running processes and to represent them intelligently to users. It's not a full-featured debugger (a full-featured debugger would never scale to 208k cores), but it will tell you whi...
Two-way encryption: I need to store passwords that can be retrieved
...ption cycle takes about 1/2 second on my machine).
Now, as to point 3 from the first list, what that would give you is a function like this:
function makeKey($userKey, $serverKey, $userSuppliedKey) {
$key = hash_hmac('sha512', $userKey, $serverKey);
$key = hash_hmac('sha512', $key, $us...
Opposite of %in%: exclude rows with values specified in a vector
... variable V1 in a data frame D1 can have values represented by the letters from A to Z. I want to create a subset D2, which excludes some values, say, B, N and T. Basically, I want a command which is the opposite of %in%
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Performance of Java matrix math libraries? [closed]
...d of course write your own native library with those optimisations to call from Java).
So what does all this mean? Well:
in principle, it is worth hunting around for a better-performing library, though unfortunately I can't recomend one
if performance is really critical to you, I would consider j...