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Checking if a double (or float) is NaN in C++
...nly if f is NaN.
Note that, as some comments below have pointed out, not all compilers respect this when optimizing code.
For any compiler which claims to use IEEE floating point, this trick should work. But I can't guarantee that it will work in practice. Check with your compiler, if in doubt.
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Cannot resolve the collation conflict between “SQL_Latin1_General_CP1_CI_AS” and “Latin1_General_CI_
...lations are needed and used when ordering and comparing strings. It's generally a good idea to have a single, unique collation used throughout your database - don't use different collations within a single table or database - you're only asking for trouble....
Once you've settled for one single col...
Vagrant ssh authentication failure
...verriding the old one: mv .ssh/id_rsa.pub .ssh/authorized_keys.
Reload ssh service in case needed: sudo service ssh reload.
Copy the private key file (by default id_rsa) to the host machine: for instance, use a fine combination of cat and clipboard, cat .ssh/id_rsa, paint and copy (better ways must ...
What's the difference between echo, print, and print_r in PHP?
...s, although such usage is rare; echo is slightly faster than print. (Personally, I always use echo, never print.)
var_dump prints out a detailed dump of a variable, including its type and the type of any sub-items (if it's an array or an object). print_r prints a variable in a more human-readable f...
Delete files older than 15 days using PowerShell
...is in the title of this post), but here's some code that will first delete all of the files older than 15 days, and then recursively delete any empty directories that may have been left behind. My code also uses the -Force option to delete hidden and read-only files as well. Also, I chose to not use...
How to send an email with Gmail as provider using Python?
...smtp.gmail.com:587')
server.ehlo()
server.starttls()
Also you should really create From:, To: and Subject: message headers, separated from the message body by a blank line and use CRLF as EOL markers.
E.g.
msg = "\r\n".join([
"From: user_me@gmail.com",
"To: user_you@gmail.com",
"Subject:...
Socket File “/var/pgsql_socket/.s.PGSQL.5432” Missing In Mountain Lion (OS X Server)
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Check for the status of the database:
service postgresql status
If the database is not running, start the db:
sudo service postgresql start
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What Automatic Resource Management alternatives exist for Scala?
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For now Scala 2.13 has finally supported: try with resources by using Using :), Example:
val lines: Try[Seq[String]] =
Using(new BufferedReader(new FileReader("file.txt"))) { reader =>
Iterator.unfold(())(_ => Option(reader.readLine()).ma...
PHP - how to best determine if the current invocation is from CLI or web server?
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A small caveat about this method: it will not return "cli" when run from a cron job. There's a number od differents keys to choose from inside of $_SERVER to determine more reliably whether the request came via HTTP or not.
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Best practice using NSLocalizedString
I'm (like all others) using NSLocalizedString to localize my app.
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