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Why were pandas merges in python faster than data.table merges in R in 2012?
...els) is large: 10,000.
Does Rprof() reveal most of the time spent in the call sortedmatch(levels(i[[lc]]), levels(x[[rc]])? This isn't really the join itself (the algorithm), but a preliminary step.
Recent efforts have gone into allowing character columns in keys, which should resolve that issue ...
DbArithmeticExpression arguments must have a numeric common type
... the operation move out the arithmetic in question from the Lambda?
After all clientDateTime and time24 are fix values so their difference does not need to be recalculated in every iteration.
Like:
TimeSpan time24 = new TimeSpan(24, 0, 0);
TimeSpan time18 = new TimeSpan(18, 0, 0);
var client...
Where does this come from: -*- coding: utf-8 -*-
... the text editor. Until now, I never knew that the python interpreter actually parsed the comment if it is present on the first two lines of the file.
– umeboshi
Dec 26 '14 at 3:08
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How to implement a unique index on two columns in rails
...st can remove the indexes who were just for one column or if I have to use all three indexes:
1 Answer
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TargetedPatchingOptOut: “Performance critical to inline across NGen image boundaries”?
...le:
String.Equals has [TargetedPatchingOptOut]
You write a program that calls String.Equals
You run NGen on this program for maximum performance
NGen will inline the String.Equals call, replacing the method call instruction with the actual code in the method.
Method calls are (slightly) expensive,...
When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
... a way of isolating one part of the script from another, but submitting it all in one block.
BEGIN and END are just like { and } in C/++/#, Java, etc.
They bound a logical block of code. I tend to use BEGIN and END at the start and end of a stored procedure, but it's not strictly necessary ther...
Mongo: find items that don't have a certain field
...rpret it as the field has to be equal to null and not missing. This is actually unexpected behavior, because you wouldn't be able to do the same for 0 (which is also false), so null is kind of the exception here. Therefore, best practice is the more readable answer using $exists: false which is not ...
Is there a jQuery unfocus method?
...ht or make my text input un-focused. I knew .blur() existed but I didn't really understand the correct syntax for this usage. +1
– Partack
Jul 10 '13 at 21:32
7
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AttributeError: 'module' object has no attribute 'tests'
...
I finally figured it out working on another problem. The problem was that my test couldn't find an import.
It looks like you get the above error if your test fails to import. This makes sense because the test suite can't import ...
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...