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Difference between as.POSIXct/as.POSIXlt and strptime for converting character vectors to POSIXct/PO

...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
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Do try/catch blocks hurt performance when exceptions are not thrown?

... { Console.WriteLine(ex.ToString()); } finally { d = Math.Sin(d); } } w.Stop(); Console.Write(" try/catch/finally: "); Console.WriteLine(w.ElapsedMilliseconds); w.Reset(); d = 0; w.Start(); for (int i = ...
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What does new self(); mean in PHP?

... the parent class The first situation would look like this (I've removed all non-necessary code, for this example -- you'll have to add it back to get the singleton behavior)* : class MyParentClass { } class MyChildClass extends MyParentClass { public static function getInstance() { ...
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How to use the “number_to_currency” helper method in the model rather than view?

... It’s not available because its use in a model (typically) violates MVC (and it does seem to in your case). You're taking data and manipulating it for presentation. This, by definition, belongs in the view, not the model. Here are some solutions: Use a presenter or view mode...
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Detecting Unsaved Changes

...reunload methods as required. From the comments, the following references all input fields, without duplicating code: $(':input').change(function () { Using $(":input") refers to all input, textarea, select, and button elements. ...
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Difference between dispatch_async and dispatch_sync on serial queue?

... I do mean serial execution. In point of view that all tasks are executed serial regards to other tasks in the same queue. Of cause it still can be concurrent regards to other queues. It is the whole point of GCD that tasks can be dispatched and executed concurrently. ...
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How to compare variables to undefined, if I don’t know whether they exist? [duplicate]

...s a string, and doesn't generate an error if the variable doesn't exist at all. share | improve this answer | follow | ...
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Rails check if yield :area is defined in content_for

... not really necessary to create a helper method: <% if @content_for_sidebar %> <div id="sidebar"> <%= yield :sidebar %> </div> <% end %> then of course in your view: <% content_for :sideb...
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In Javascript/jQuery what does (e) mean?

... answered Apr 19 '17 at 9:32 Jason LiuJason Liu 4944 bronze badges ...
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What do the result codes in SVN mean?

... U: Working file was updated G: Changes on the repo were automatically merged into the working copy M: Working copy is modified C: This file conflicts with the version in the repo ?: This file is not under version control !: This file is under version control but is mis...