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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. share | ...
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How do I convert a String object into a Hash object?

... The string created by calling Hash#inspect can be turned back into a hash by calling eval on it. However, this requires the same to be true of all of the objects in the hash. If I start with the hash {:a => Object.new}, then its string represen...
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Reset Entity-Framework Migrations

... I used IgnoreChanges on the initial migration, but now I want to delete all my migrations and start with an initial migration with all of the logic. ...
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Is it expensive to use try-catch blocks even if an exception is never thrown?

... try has almost no expense at all. Instead of doing the work of setting up the try at runtime, the code's metadata is structured at compile time such that when an exception is thrown, it now does a relatively expensive operation of walking up the stack an...
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What is the purpose of std::make_pair vs the constructor of std::pair?

... Actually, the types should be deduced at compile time without the need to specify. – Chad Feb 14 '12 at 1:51 ...
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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?

...ld instances (at least, not at the moment). If a base class has a field called author, you cannot create another model field called author in any class that inherits from that base class. share | ...
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How to read if a checkbox is checked in PHP?

... this is the really good form to do this in pure simple php. but have to note that the value of a checkbox is string on when it is activated an a inexisting value if it is checked. – Elvis Technologies ...
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Unit Testing AngularJS directive with templateUrl

... You're correct that it's related to ngMock. The ngMock module is automatically loaded for every Angular test, and it initializes the mock $httpBackend to handle any use of the $http service, which includes template fetching. The template system tries to load the template through $http and it become...
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Trouble comparing time with RSpec

...olution. I think it's easier and more reliable to just create the date manually: it "updates updated_at attribute" do freezed_time = Time.utc(2015, 1, 1, 12, 0, 0) #Put here any time you want Timecop.freeze(freezed_time) do patch :update @article.reload expect(@article.updated_at).t...
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Preloading images with JavaScript

Is the function I wrote below enough to preload images in most, if not all, browsers commonly used today? 14 Answers ...