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How are feature_importances in RandomForestClassifier determined?

...d in [1] (often cited, but unfortunately rarely read...). It is sometimes called "gini importance" or "mean decrease impurity" and is defined as the total decrease in node impurity (weighted by the probability of reaching that node (which is approximated by the proportion of samples reaching that no...
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How to determine the version of the C++ standard used by the compiler?

... By my knowledge there is no overall way to do this. If you look at the headers of cross platform/multiple compiler supporting libraries you'll always find a lot of defines that use compiler specific constructs to determine such things: /*Define Microsoft V...
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Define css class in django Forms

... The only sane solution, I must say. Thank you!. Python code, and especially in form's definition, is the last place to put stuff for styling - these definitely belong to the templates. – Boris Chervenkov Nov 12 '11 at 23:09 ...
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Underscore: sortBy() based on multiple attributes

... said, that's pretty hacky. To do this properly you'd probably want to actually use the core JavaScript sort method: patients.sort(function(x, y) { var roomX = x[0].roomNumber; var roomY = y[0].roomNumber; if (roomX !== roomY) { return compare(roomX, roomY); } return compare(x[0].name...
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How do I create an average from a Ruby array?

...void integer division or your results will be wrong. Also, this isn't generally applicable to every possible element type (obviously, an average only makes sense for things that can be averaged). But if you want to go that route, use this: class Array def sum inject(0.0) { |result, el| result...
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How to resize superview to fit all subviews with autolayout?

...n a UITableViewCell (to determine row height for example) then you should call it against your cell contentView and grab the height. Further considerations exist if you have one or more UILabel's in your view that are multiline. For these it is imperitive that the preferredMaxLayoutWidth propert...
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Algorithm to detect corners of paper sheet in photo

...n are awesome, move to them as soon as possible. :D Instead of removing small objects and or noise, lower the canny restraints, so it accepts more edges, and then find the largest closed contour (in OpenCV use findcontour() with some simple parameters, I think I used CV_RETR_LIST). might still stru...
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Why is it slower to iterate over a small string than a small list?

...nd with timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time. ...
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What's the best UI for entering date of birth? [closed]

...ry fast. For a not so advanced user I suggest using a datepicker. Since usually you also have advanced and non-advanced users I suggest a combination of text input and datepicker. share | improve th...
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How do I use prepared statements in SQlite in Android?

... I use prepared statements in Android all the time, it's quite simple : SQLiteDatabase db = dbHelper.getWritableDatabase(); SQLiteStatement stmt = db.compileStatement("INSERT INTO Country (code) VALUES (?)"); stmt.bindString(1, "US"); stmt.executeInsert(); ...