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What's the difference between IQueryable and IEnumerable
...;>), which can be thought of as "is the 'Age' property > 18".
This allows things like LINQ-to-SQL to exist because they can parse the expression tree and convert it into equivalent SQL. And because the provider doesn't need to execute until the IQueryable is enumerated (it implements IEnum...
Using lambda expressions for event handlers
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Really? Interesting - so, if I register two anonymous functions that look the same (w.l.o.g. have an empty body), and then I unregister (using -=) another anonymous function that too has an empty body, it is essentially undefin...
Finding the path of the program that will execute from the command line in Windows
Say I have a program X.EXE installed in folder c:\abcd\happy\ on the system. The folder is on the system path. Now suppose there is another program on the system that's also called X.EXE but is installed in folder c:\windows\ .
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Why does (“foo” === new String(“foo”)) evaluate to false in JavaScript?
I was going to start using === (triple equals, strict comparison) all the time when comparing string values, but now I find that
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How do I determine the size of an object in Python?
...turn the size of an object in bytes.
The object can be any type of object.
All built-in objects will return
correct results, but this does not
have to hold true for third-party
extensions as it is implementation
specific.
Only the memory consumption directly attributed to the object is
accounted for...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
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They are essentially equivalent to each other (in fact this is how some databases implement DISTINCT under the hood).
If one of them is faster, it's going to be DISTINCT. This is because, although the two are the same, a query optimizer wo...
I want my android application to be only run in portrait mode?
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In the manifest, set this for all your activities:
<activity android:name=".YourActivity"
android:configChanges="orientation"
android:screenOrientation="portrait"/>
Let me explain:
With android:configChanges="orientation" you tell Andro...
Emulate ggplot2 default color palette
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It is just equally spaced hues around the color wheel, starting from 15:
gg_color_hue <- function(n) {
hues = seq(15, 375, length = n + 1)
hcl(h = hues, l = 65, c = 100)[1:n]
}
For example:
n = 4
cols = gg_color_hue(n)
dev.new(...
How to invoke the super constructor in Python?
In all other languages I've worked with the super constructor is invoked implicitly. How does one invoke it in Python? I would expect super(self) but this doesn't work.
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How to fire AJAX request Periodically?
...the page after every 5 seconds. But I want to do it using jQuery and AJAX call. Is it possible?
4 Answers
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