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Java concurrency: Countdown latch vs Cyclic barrier
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One major difference is that CyclicBarrier takes an (optional) Runnable task which is run once the common barrier condition is met.
It also allows you to get the number of clients waiting at the barrier and the number required to...
Set margin size when converting from Markdown to PDF with pandoc
... Next, I used pandoc to convert the .md file into a PDF file (I get an error if I try and convert from the .html file). However, the PDF that is produced have massive margins (like this http://johnmacfarlane.net/pandoc/demo/example13.pdf ). How can I get pandoc to produce something with smaller ...
Composite Key with EF 4.1 Code First
...u can mark both ActivityID and ActivityName properties with Key annotation or you can use fluent API as described by @taylonr.
Edit:
This should work - composite key defined with annotations requires explicit column order:
public class ActivityType
{
[Key, Column(Order = 0)]
public int Ac...
kernel stack and user space stack
...ack is used? If a local variable is declared in an ISR, where it will be stored? Does each process has its own kernel stack? Then how the process coordinates between both these stacks?
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Why is __dirname not defined in node REPL?
From the node manual I see that I can get the directory of a file with __dirname , but from the REPL this seems to be undefined. Is this a misunderstanding on my side or where is the error?
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What is the maximum length of latitude and longitude? [closed]
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If latitude coordinate is reported as -6.3572375290155 or -63.572375290155 in decimal degrees then you could round-off and store up to 6 decimal places for 10 cm (or 0.1 meter) precision.
Overview
The valid range of latitude in degrees is ...
How to use null in switch
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This is not possible with a switch statement in Java. Check for null before the switch:
if (i == null) {
doSomething0();
} else {
switch (i) {
case 1:
// ...
break;
}
}
You can't use arbitrary objects in switch statements*. The reason that the compile...
*.h or *.hpp for your class definitions
I've always used a *.h file for my class definitions, but after reading some boost library code, I realised they all use *.hpp . I've always had an aversion to that file extension, I think mainly because I'm not used to it.
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What is the difference between Θ(n) and O(n)?
...s it just laziness of typing because nobody knows how to type this symbol, or does it mean something different?
9 Answers
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How to add an extra column to a NumPy array
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I think a more straightforward solution and faster to boot is to do the following:
import numpy as np
N = 10
a = np.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
...