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The new syntax “= default” in C++11
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A defaulted default constructor is specifically defined as being the same as a user-defined default constructor with no initialization list and an empty compound statement.
§12.1/6 [class.ctor] A default constructor that is defaulted and not defined as deleted is im...
How do you find all subclasses of a given class in Java?
How does one go about and try to find all subclasses of a given class (or all implementors of a given interface) in Java?
As of now, I have a method to do this, but I find it quite inefficient (to say the least).
The method is:
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Speed up the loop operation in R
...Biggest problem and root of ineffectiveness is indexing data.frame, I mean all this lines where you use temp[,].
Try to avoid this as much as possible. I took your function, change indexing and here version_A
dayloop2_A <- function(temp){
res <- numeric(nrow(temp))
for (i in 1:nrow(te...
Break parallel.foreach?
How do I break out of an parallel.for loop?
5 Answers
5
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Lock Escalation - What's happening here?
... to take fewer, larger locks (e.g. entire table) instead of locking many smaller things (e.g. row locks).
But this can be problematic when you have a huge table, because taking a lock on the entire table may lock out other queries for a long time. That's the tradeoff: many small-granularity locks...
Memory footprint of Haskell data types
... GHC creates a single instance of these constructors and shares it amongst all uses.
A word is 4 bytes on a 32-bit machine, and 8 bytes on a 64-bit machine.
So e.g.
data Uno = Uno a
data Due = Due a b
an Uno takes 2 words, and a Due takes 3.
The Int type is defined as
data Int = I# Int#
no...
How to discard all changes made to a branch?
...e. design ) and I've made a number of changes, but I need to discard them all and reset it to match the repository version. I thought git checkout design would do it, but it just tells me I'm already in branch design and that I have 3 modified files.
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SQL: IF clause within WHERE clause
...n a WHERE clause. If you want to apply some "IF" logic in the WHERE clause all you need to do is add the extra condition with an boolean AND to the section where it needs to be applied.
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Finding all possible permutations of a given string in python
I have a string. I want to generate all permutations from that string, by changing the order of characters in it. For example, say:
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JSON.parse vs. eval()
... and json.parse just parses JSON whereas eval would leave the door open to all JS expressions.
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