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What is the difference between a deep copy and a shallow copy?
What is the difference between a deep copy and a shallow copy?
31 Answers
31
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PostgreSQL error: Fatal: role “username” does not exist
...I can't do anything with PostgreSQL: can't createdb , can't createuser ; all operations return the error message
15 Answe...
Cluster analysis in R: determine the optimal number of clusters
...lidean",
method = "kmeans", min.nc=2, max.nc=15,
index = "alllong", alphaBeale = 0.1)
hist(nb$Best.nc[1,], breaks = max(na.omit(nb$Best.nc[1,])))
# Looks like 3 is the most frequently determined number of clusters
# and curiously, four clusters is not in the output at all!
If yo...
Get the device width in javascript
...th property.
Sometimes it's also useful to use window.innerWidth (not typically found on mobile devices) instead of screen width when dealing with desktop browsers where the window size is often less than the device screen size.
Typically, when dealing with mobile devices AND desktop browsers I use...
Can I avoid the native fullscreen video player with HTML5 on iPhone or android?
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In iOS 10+
Apple enabled the attribute playsinline in all browsers on iOS 10, so this works seamlessly:
<video src="file.mp4" playsinline>
In iOS 8 and iOS 9
Short answer: use iphone-inline-video, it enables inline playback and syncs the audio.
Long answer: You can wo...
One line if-condition-assignment
...
I don't think this is possible in Python, since what you're actually trying to do probably gets expanded to something like this:
num1 = 20 if someBoolValue else num1
If you exclude else num1, you'll receive a syntax error since I'm quite sure that the assignment must actually return so...
Hide/Show Column in an HTML Table
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I would like to do this without attaching a class to every td
Personally, I would go with the the class-on-each-td/th/col approach. Then you can switch columns on and off using a single write to className on the container, assuming style rules like:
table.hide1 .col1 { display: none; }
table...
How to stop a program running under Eclipse?
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Keep in mind that on Android, programs generally only 'stop' if you finish() or the system destroys them when memory is required. Why stop at all? You do not need to stop to fix/re-install/re-test, for example.
...
Creating an index on a table variable
...ds of adding constraint based indexes discussed below SQL Server 2014 also allows non unique indexes to be specified directly with inline syntax on table variable declarations.
Example syntax for that is below.
/*SQL Server 2014+ compatible inline index syntax*/
DECLARE @T TABLE (
C1 INT INDEX IX...
Git: How to update/checkout a single file from remote origin master?
...fetch
git checkout origin/master -- path/to/file
The fetch will download all the recent changes, but it will not put it in your current checked out code (working area).
The checkout will update the working tree with the particular file from the downloaded changes (origin/master).
At least this w...