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How to rollback just one step using rake db:migrate
...think using VERSION=n is the right way to do that, but I don't know the correct value of n to use. Is there any command to check the current n value?
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How to send an email using PHP?
...sing PHP's mail() function it's possible. Remember mail function will not work on a Local server.
<?php
$to = 'nobody@example.com';
$subject = 'the subject';
$message = 'hello';
$headers = 'From: webmaster@example.com' . "\r\n" .
'Reply-To: webmaster@example.com' . "\r\n" .
'X-Maile...
Why doesn't JavaScript support multithreading?
Is it a deliberate design decision or a problem with our current day browsers which will be rectified in the coming versions?
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How to exclude file only from root folder in Git
I am aware of using .gitignore file to exclude some files being added, but I have several config.php files in source tree and I need to exclude only one, located in the root while other keep under revision control.
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Why rgb and not cmy? [closed]
Seeing as how the three primary colors are cyan, magenta and yellow (CMY), why do monitors and almost all the GUI components out there use red, green and blue (RGB)? (If I'm not mistaken, printers use the CMYK model.)
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How do I see the last 10 commits in reverse-chronological order with SVN?
...t X number of commits along with commit messages, in reverse-chronological order (newest commit first)?
4 Answers
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If a folder does not exist, create it
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As others have said, use System.IO.Directory.CreateDirectory
But, you don't need to check if it exists first. From the docs
Any and all directories specified in path are created, unless they already exist or unless some part of path is invalid. If the director...
NGinx Default public www location?
I have worked with Apache before, so I am aware that the default public web root is typically /var/www/ .
30 Answers
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Performance of Java matrix math libraries? [closed]
...e taken was again around 4 seconds as JBLAS uses multithreaded ATLAS.
So for me it was clear that the Java libraries didn't perform too well. However if someone has to code in Java, then the best option is JBLAS. Jama, Colt and Parallel Colt are not fast.
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The “backspace” escape character '\b': unexpected behavior?
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Your result will vary depending on what kind of terminal or console program you're on, but yes, on most \b is a nondestructive backspace. It moves the cursor backward, but doesn't erase what's there.
So for the hello worl part, the code outputs
hello worl
^
...(where...