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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
...
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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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.
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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...
Strengths of Shell Scripting compared to Python [closed]
...programs in shell.
Shell scripting reuses entire programs.
Shell is universally available (on anything like Unix) - Python is not necessarily installed.
'Tis true that you can do everything in Python that you can do in shell; 'tis also true that there are things that are easy in Python that are ha...
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...
Overwriting my local branch with remote branch [duplicate]
...n
update your list of remote branches and sync new commits:
git fetch --all
then, reset your branch to the point where origin/branch points to:
git reset --hard origin/branch
be careful, this will remove any changes from your working tree!
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