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How to initialize a dict with keys from a list and empty value in Python?
...dict.fromkeys([1, 2, 3], []), all of the keys are mapped to the same list, and modifying one will modify them all.
– charleslparker
Jun 26 '13 at 16:47
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PostgreSQL: Is it better to use multiple databases with one schema each, or one database with multip
... will work with no trouble. So you definitely want to go with one database and multiple schemas within that database.
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what exactly is device pixel ratio?
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Short answer
The device pixel ratio is the ratio between physical pixels and logical pixels. For instance, the iPhone 4 and iPhone 4S report a device pixel ratio of 2, because the physical linear resolution is double the logical linear resolution.
Physical resolution: 960 x 640
Logical resolutio...
Loop code for each file in a directory [duplicate]
I have a directory of pictures that I want to loop through and do some file calculations on. It might just be lack of sleep, but how would I use PHP to look in a given directory, and loop through each file using some sort of for loop?
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Git push branch from one remote to another?
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@patthoyts I tried the mentioned command it says everything up to date, But I have 10 branches in remote A and 6 branches in remote B so can you please tell me how can I move the left out branches?
– Keshav1234
Jan 3 '18 at...
Determining Referer in PHP
What is the most reliable and secure way to determine what page either sent, or called (via AJAX), the current page. I don't want to use the $_SERVER['HTTP_REFERER'] , because of the (lack of) reliability, and I need the page being called to only come from requests originating on my site.
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Execution time of C program
...Windows machines (from the Win98 era) it was closer to 60ms.
clock() is standard C; it works "everywhere". There are system-specific functions, such as getrusage() on Unix-like systems.
Java's System.currentTimeMillis() does not measure the same thing. It is a "wall clock": it can help you measure...
Use of Application.DoEvents()
...same kind of wisdom as "don't mutate a struct". Erm, why does the runtime and the language supports mutating a struct if that's so bad? Same reason: you shoot yourself in the foot if you don't do it right. Easily. And doing it right requires knowing exactly what it does, which in the case of DoE...
How to convert a scala.List to a java.util.List?
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Scala List and Java List are two different beasts, because the former is immutable and the latter is mutable. So, to get from one to another, you first have to convert the Scala List into a mutable collection.
On Scala 2.7:
import sca...
HTTP vs HTTPS performance
Are there any major differences in performance between http and https? I seem to recall reading that HTTPS can be a fifth as fast as HTTP. Is this valid with the current generation webservers/browsers? If so, are there any whitepapers to support it?
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