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Static variables in member functions
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169
Since class A is a non-template class and A::foo() is a non-template function. There will be o...
Why does X[Y] join of data.tables not allow a full outer join, or a left join?
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To quote from the data.table FAQ 1.11 What is the difference between X[Y] and merge(X, Y)?
X[Y] is a join, looking up X's rows using Y (or Y's key if it has one) as an index.
Y[X] is a join, looking up Y's rows using X (or X's key if it has one)
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Is it possible to view RabbitMQ message contents directly from the command line?
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107
You should enable the management plugin.
rabbitmq-plugins enable rabbitmq_management
See he...
binning data in python with scipy/numpy
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184
It's probably faster and easier to use numpy.digitize():
import numpy
data = numpy.random.ran...
Why is Go so slow (compared to Java)?
As we could see from The Computer Language Benchmarks Game in 2010:
10 Answers
10
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OS X Terminal Colors [closed]
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751
Here is a solution I've found to enable the global
terminal colors.
Edit your .bash_profile (si...
Analyze audio using Fast Fourier Transform
...ly spaced frequencies, starting at 0. Because your sampling frequency is 44100 samples / sec. and the number of points in your FFT is 256, your frequency spacing is 44100 / 256 = 172 Hz (approximately)
The first coefficient in your array will be the 0 frequency coefficient. That is basically the av...
Running a cron job at 2:30 AM everyday
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541
crontab -e
add:
30 2 * * * /your/command
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MongoDB Aggregation: How to get total records count?
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13 Answers
13
Active
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Signed to unsigned conversion in C - is it always safe?
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Your i will be converted to an unsigned integer by adding UINT_MAX + 1, then the addition will be carried out with the unsigned values, resulting in a large result (depending on the values of u and i).
Long Answer
According to the C99 Standard:
6.3.1.8 Usual arithmetic conversions
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