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How efficient is locking an unlocked mutex? What is the cost of a mutex?
...ss to the object happens often, then multiple locks would increase parallelism. At the cost of maintainability, since more locking means more debugging of the locking.
How efficient is it to lock a mutex? I.e. how much assembler instructions are there likely and how much time do they take (in th...
How does `is_base_of` work?
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If they are related
Let's for a moment assume that B is actually a base of D. Then for the call to check, both versions are viable because Host can be converted to D* and B*. It's a user defined conversion sequence as described by 13.3.3.1.2 from Host<B, D> to D* and B* r...
Why is XOR the default way to combine hashes?
... you want to combine them. I've read that a good way to combine two hashes is to XOR them, e.g. XOR( H(A), H(B) ) .
9 An...
How important is the order of columns in indexes?
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Look at an index like this:
Cols
1 2 3
-------------
| | 1 | |
| A |---| |
| | 2 | |
|---|---| |
| | | |
| | 1 | 9 |
| B | | |
| |---| |
| | 2 | |
| |---| |
| | 3 | |
|---|---| |
See how restricting...
Is an array name a pointer?
Is an array's name a pointer in C?
If not, what is the difference between an array's name and a pointer variable?
10 Answer...
Why does one use dependency injection?
...cy injections (DI), and once again I failed. It just seems silly. My code is never a mess; I hardly write virtual functions and interfaces (although I do once in a blue moon) and all my configuration is magically serialized into a class using json.net (sometimes using an XML serializer).
...
'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
What explains the difference in behavior of boolean and bitwise operations on lists vs NumPy arrays?
8 Answers
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Why java.lang.Object is not abstract? [duplicate]
Why is the Object class, which is base class of 'em all in Java, not abstract?
14 Answers
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What is the difference between linear regression and logistic regression?
When we have to predict the value of a categorical (or discrete) outcome we use logistic regression . I believe we use linear regression to also predict the value of an outcome given the input values.
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Cleaning `Inf` values from an R dataframe
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Option 1
Use the fact that a data.frame is a list of columns, then use do.call to recreate a data.frame.
do.call(data.frame,lapply(DT, function(x) replace(x, is.infinite(x),NA)))
Option 2 -- data.table
You could use data.table and set. This avoids some internal...