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Why is `[` better than `subset`?
...ct 'cyl' not found
because R no longer "knows" where to find the object called 'cyl'. He also points out the truly bizarre stuff that can happen if by chance there is an object called 'cyl' in the global environment:
cyl <- 4
subscramble(mtcars, cyl == 4)
cyl <- sample(10, 100, rep = T)
su...
Create empty file using python [duplicate]
...mknod("newfile.txt") (but it requires root privileges on OSX). The system call to create a file is actually open() with the O_CREAT flag. So no matter how, you'll always open the file.
So the easiest way to simply create a file without truncating it in case it exists is this:
open(x, 'a').close()
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Difference between == and === in JavaScript [duplicate]
...esponding positions.
Two numbers are strictly equal when they are numerically equal (have
the same number value). NaN is not
equal to anything, including NaN.
Positive and negative zeros are equal
to one another.
Two Boolean operands are strictly equal if both are true or
both are fals...
\r\n, \r and \n what is the difference between them? [duplicate]
... \r is for Mac OS 9 and under (also back in the days when it was called System). Mac OS X mostly uses \n (and is a Unix).
– Bruno
Mar 15 '13 at 13:51
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I cannot start SQL Server browser
...system account and not this account.
then apply and chose automatic and finally run the server.
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How do I create a dictionary with keys from a list and values defaulting to (say) zero? [duplicate]
...that if 0 is mutable (e.g. list or dict), you get into trouble, because it all refers to the same memory location. For this reason, the accepted answer is safer.
– NumesSanguis
Oct 25 '19 at 7:00
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How To Set Text In An EditText
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What might confuse a newbie is that setText actually takes a CharSequence and a BufferType. So it's useful to remember that Strings are CharSequence's
– Avatar33
Jun 11 '16 at 9:51
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multi-layer perceptron (MLP) architecture: criteria for choosing number of hidden layers and size of
...echnique, then always start with one hidden layer. Almost certainly that's all you will need. If your data is separable using a MLP, then that MLP probably only needs a single hidden layer. There is theoretical justification for this, but my reason is purely empirical: Many difficult classification...
How to stop Jenkins installed on Mac Snow Leopard?
I have installed Jenkins executable on OSX, but now I want to stop it running. Whenever I kill it, no matter how, it just restarts immediately.
...
How to pass parameters correctly?
... Are there any best practices of how to send parameters in C++ because I really find it, let's say, not trivial
If your function needs to modify the original object being passed, so that after the call returns, modifications to that object will be visible to the caller, then you should pass by lva...