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What does character set and collation mean exactly?
... lowercase and uppercase letters are
equivalent? Then we would have at
least two rules: (1) treat the
lowercase letters 'a' and 'b' as
equivalent to 'A' and 'B'; (2) then
compare the encodings. We call this a
case-insensitive collation. It's a
little more complex than a binary
collat...
What are the underlying data structures used for Redis?
... only show up once. Sets are great for lazily ensuring something exists at least once without worrying about duplicate elements accumulating and wasting space. You can add the same string as many times as you like without needing to check if it already exists.
Sets are fast for membership checking, ...
How can I index a MATLAB array returned by a function without first assigning it to a local variable
...
At least in MATLAB 2013a you can use getfield like:
a=rand(5);
getfield(a,{1,2}) % etc
to get the element at (1,2)
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How to add minutes to my Date
... or noon in Québec? If you meant noon in Pakistan, say so by including at least the offset-from-UTC (+05:00), and better still, the name of the time zone (Asia/Karachi).
Instant
If you want the same moment as seen through the lens of UTC, extract an Instant. The Instant class represents a moment ...
Replace one substring for another string in shell script
...t_string/Suzi/$second_string}
It's portable to Windows and works with at least as old as Bash 3.1.
To show you don't need to worry much about escaping let's turn this:
/home/name/foo/bar
Into this:
~/foo/bar
But only if /home/name is in the beginning. We don't need sed!
Given that bash giv...
Node.js app can't run on port 80 even though there's no other process blocking the port
...ty implications if you are on a shared network. You might want to apply at least some level of additional security (disable password & root login).
I personally only ever use this on my local machine. I'm not sure how it affects the processing speed of your requests if you run this on productio...
Python logging: use milliseconds in time format
...tion of ct to make it a datetime object instead of a struct_time, then (at least with modern versions of Python) we can call ct.strftime and then we can use %f to format microseconds:
import logging
import datetime as dt
class MyFormatter(logging.Formatter):
converter=dt.datetime.fromtimestamp...
Can I safely delete contents of Xcode Derived data folder?
...
$ du -h -d=1 ~/Library/Developer/Xcode/*
shows at least two folders are huge:
1.5G /Users/horace/Library/Developer/Xcode/DerivedData
9.4G /Users/horace/Library/Developer/Xcode/iOS DeviceSupport
Feel free to remove stuff in the folders:
rm -rf ~/Library/Developer/X...
What is thread contention?
...access either the same resource or related resources in such a way that at least one of the contending threads runs more slowly than it would if the other thread(s) were not running.
The most obvious example of contention is on a lock. If thread A has a lock and thread B wants to acquire that same ...
What happened to “HelveticaNeue-Italic” on iOS 7.0.3
... run italicSystemFontOfSize:, which should always return something, and at least avoid a crash.
– SaltyNuts
Nov 6 '13 at 15:11
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