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mongodb group values by multiple fields
... $slice just off the basic aggregation result. For "large" results, run parallel queries instead for each grouping ( a demonstration listing is at the end of the answer ), or wait for SERVER-9377 to resolve, which would allow a "limit" to the number of items to $push to an array.
db.books.aggregate(...
Get the position of a div/span tag
...n will tell you the x,y position of the element relative to the page. Basically you have to loop up through all the element's parents and add their offsets together.
function getPos(el) {
// yay readability
for (var lx=0, ly=0;
el != null;
lx += el.offsetLeft, ly += el.off...
JavaScript to scroll long page to DIV
...ding to the great compatibility-tables on quirksmode, this is supported by all major browsers!
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Dynamically Changing log4j log level
What are the different approaches for changing the log4j log level dynamically, so that I will not have to redeploy the application. Will the changes be permanent in those cases?
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Adding Core Data to existing iPhone project
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All the CoreData header files are imported in App_Prefix.pch, so the CoreData classes will be available throughout your Project, so you don't have to manually import the header in the files you need them.
So open up Xcode an...
How to extract the decision rules from scikit-learn decision-tree?
...sion of sklearn, because some values of tree.tree_.feature are -2 (specifically for leaf nodes).
There is no need to have multiple if statements in the recursive function, just one is fine.
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Create instance of generic type whose constructor requires a parameter?
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@JonSkeet: If I exposed the API with .NET generic to be called in VB6.0..Does it still workable?
– Roy Lee
Dec 13 '12 at 7:52
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Getting list of parameter names inside python function [duplicate]
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Well we don't actually need inspect here.
>>> func = lambda x, y: (x, y)
>>>
>>> func.__code__.co_argcount
2
>>> func.__code__.co_varnames
('x', 'y')
>>>
>>> def func2(x,y=3):
... print(...
How to add a jar in External Libraries in android studio
...pile files('libs/library_name.jar') in build.gradle [You don't have to manually enter this in your build file].
Now you can start using the library in your project.
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Version of SQLite used in Android?
...rt it.
Note: if you want your app to use the same version of SQLite across all Android versions, consider using this 3rd party SQLite support library.
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