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Get type of all variables
...(c(TRUE, FALSE)) #a vector containing only logicals: logical
#R is really cramping my style, killing my high, irritation is increasing:
typeof(factor()) #an empty factor has default type: integer
typeof(factor(3.14)) #a factor containing doubles: integer
typeof(factor(...
How can I use grep to find a word inside a folder?
..., a directory is a kind of file (there is a term "regular file" to specifically refer to entities that are called just "files" in Windows).
grep -nr string reads the content to search from the standard input, that is why it just waits there for input from you, and stops doing so when you press ^C (...
Open firewall port on CentOS 7
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Use this command to find your active zone(s):
firewall-cmd --get-active-zones
It will say either public, dmz, or something else. You should only apply to the zones required.
In the case of public try:
firewall-cmd --zone=public --add-port=2888/tcp --permanent
Then reme...
When to use MyISAM and InnoDB? [duplicate]
... -- Mostly no longer true.
Full-text indexing. -- InnoDB has it now
Especially good for read-intensive (select) tables. -- Mostly no longer true.
Disk footprint is 2x-3x less than InnoDB's. -- As of Version 5.7, this is perhaps the only real advantage of MyISAM.
InnoDB:
The InnoDB storage engi...
How to get terminal's Character Encoding
... is not good. a more complete solution would be something like: echo ${LC_ALL:-${LC_CTYPE:-${LANG}}}. then again, the variable being set isn't a guarantee that they're valid, so you should stick to the locale program (as seen in other answers here).
– Mike Frysinger
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Should I avoid the use of set(Preferred|Maximum|Minimum)Size methods in Java Swing?
...uld I use them? In which context? For what purposes?
I don't know, personally I think of it as an API design accident. Slightly forced by compound components having special ideas about child sizes. "Slightly", because they should have implemented their needs with a custom LayoutManager.
What ex...
Get int value from enum in C#
I have a class called Questions (plural). In this class there is an enum called Question (singular) which looks like this.
...
Better way of incrementing build number?
... template of Xcode?
The reason I ask this is that Project-Info.plist normally is under version control, and modifying it means that it will be marked as, well, modified.
If that is fine with you, then the following snippet will update the build number and mark the file as modified in the process...
Android: Share plain text using intent (to all messaging apps)
...ablet, I was asked to choose from the list of apps. Probably its about installing those extra apps on emulator.
– Piyush-Ask Any Difference
Mar 5 '13 at 15:57
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Are HTTPS headers encrypted?
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The whole lot is encrypted† - all the headers.
That's why SSL on vhosts doesn't work too well - you need a dedicated IP address because the Host header is encrypted.
†The Server Name Identification (SNI) standard means that the hostname may not be encr...