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Declaring and initializing variables within Java switches
...he right in the local variable declaration statement.
In your case, case 2 is in the same block as case 1 and appears after it, even though case 1 will never execute... so the local variable is in scope and available for writing despite you logically never "executing" the declaration. (A declarati...
What is the bower (and npm) version syntax?
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342
In a nutshell, the syntax for Bower version numbers (and NPM's) is called SemVer, which is short...
If vs. Switch Speed
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answered Jan 14 '09 at 23:16
Konrad RudolphKonrad Rudolph
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Should I use a data.frame or a matrix?
...e the choice.
Also:
Matrices are more memory efficient:
m = matrix(1:4, 2, 2)
d = as.data.frame(m)
object.size(m)
# 216 bytes
object.size(d)
# 792 bytes
Matrices are a necessity if you plan to do any linear algebra-type of operations.
Data frames are more convenient if you frequently refer to ...
How to pip install a package with min and max version range?
... install a package with both a minimum version ( pip install package>=0.2 ) and a maximum version which should never be installed (theoretical api: pip install package<0.3 ).
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How to swap keys and values in a hash
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286
Ruby has a helper method for Hash that lets you treat a Hash as if it was inverted (in essence...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
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It means display width
Whether you use tinyint(1) or tinyint(2), it does not make any difference.
I always use tinyint(1) and int(11), I used several mysql clients (navicat, sequel pro).
It does not mean anything AT ALL! I ran a test, all above clients or even the command-line client...
Difference between dispatch_async and dispatch_sync on serial queue?
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for this code
dispatch_async(_serialQueue, ^{ printf("1"); });
printf("2");
dispatch_async(_serialQueue, ^{ printf("3"); });
printf("4");
It may print 2413 or 2143 or 1234 but 1 always before 3
for this code
dispatch_sync(_serialQueue, ^{ printf("1"); });
printf("2");
dispatch_sync(_serialQu...
LINQ where vs takewhile
... and find all elements matching the condition
var intList = new int[] { 1, 2, 3, 4, 5, -1, -2 };
Console.WriteLine("Where");
foreach (var i in intList.Where(x => x <= 3))
Console.WriteLine(i);
Console.WriteLine("TakeWhile");
foreach (var i in intList.TakeWhile(x => x <= 3))
Conso...
Python Matplotlib figure title overlaps axes label when using twiny
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248
I'm not sure whether it is a new feature in later versions of matplotlib, but at least for 1.3...