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Efficiently test if a port is open on Linux?
... to connect by loopback. If it fails, then the port is closed or we aren't allowed access. Afterwards, close the connection.
Modify this for your use case, such as sending an email, exiting the script on failure, or starting the required service.
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Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
How to correct TypeError: Unicode-objects must be encoded before hashing?
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asmeurer
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answered Sep 28 '11 at 15:10
cwallenpoolecwallenpoole
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Why does struct alignment depend on whether a field type is primitive or user-defined?
... The documentation of StructLayoutAttribute is pretty interesting. Basically, only blittable types are controlled through StructLayout in managed memory. Interesting, never knew that.
– Michael Stum♦
Jul 15 '14 at 7:01
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Validating email addresses using jQuery and regex
...ive for asdf@adsf.com
– gcb
Apr 13 '11 at 7:30
@gcb: hi, if the regex didn't satisfy your needs you can change it, any...
Wrapping chained method calls on a separate line in Eclipse for Java
I haven't been successful in figuring out how to wrap each method call in Eclipse . For example, I have this:
7 Answers
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Making the Android emulator run faster
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Official web page
~50% faster
Windows:
Install "Intel x86 Emulator Accelerator (HAXM)" => SDK-Manager/Extras
Install "Intel x86 Atom System Images" => SDK-Manager/Android 2.3.3
Go to the Android SDK root folder and navigate to extras\intel\Hardware_Accelerated_E...
How can I reset a react component including all transitively reachable state?
I occasionally have react components that are conceptually stateful which I want to reset. The ideal behavior would be equivalent to removing the old component and readding a new, pristine component.
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How to stop and restart memcached server?
... well, it realy depends on your linux distribution and how you did install memcache. If you hav installed package of your distribution there should be memcached start/stop script (maybe it is in different directory like /etc/rc.d) If you installed memcached manualy you probably need also create ...
Using Git, how could I search for a string across all branches?
Using Git, how could I search within all files in all local branches for a given string?
5 Answers
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