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What's the best way to set a single pixel in an HTML5 canvas?

... as an exercise for the reader creating another img or canvas filled with all the pixels you want and use drawImage() to blit just the pixel you want across. This would probably be very fast, but has the limitation that you need to pre-calculate the pixels you need. Note that my tests do not atte...
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Remove elements from collection while iterating

...61-4"))); Collect and Remove The first technique consists in collecting all the objects that we want to delete (e.g. using an enhanced for loop) and after we finish iterating, we remove all found objects. ISBN isbn = new ISBN("0-201-63361-2"); List<Book> found = new ArrayList<Book>()...
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Extract a number from a string (JavaScript)

...ecific example, var thenum = thestring.replace( /^\D+/g, ''); // replace all leading non-digits with nothing in the general case: thenum = "foo3bar5".match(/\d+/)[0] // "3" Since this answer gained popularity for some reason, here's a bonus: regex generator. function getre(str, num) { ...
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How do I reset the scale/zoom of a web app on an orientation change on the iPhone?

... the landscape mode I have to double tap on something twice, first to zoom all the way in (the normal double tap behavior) and again to zoom all the way out (again, the normal double tap behavior). When it zooms out, it zooms out to the correct NEW scale for landscape mode. ...
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C++ cout hex values?

... This seems to change all future output from cout to hex; so if you only want 'a' to be printed in hex you may want something like cout << hex << a << dec; to change it back. – ShreevatsaR M...
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What is the difference between “int” and “uint” / “long” and “ulong”?

...128 to 127. The 9th bit represents 256. So with 8 bits you can represent all values up to 255 (9th val - 1). The range from -128 to 127 has a length of exactly 255. So there is no bit that holds the sign. All values up to 127 are positive. Values above get displayed negative. 255 would be -1. 254 wo...
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How do you manage databases in development, test, and production?

...of good options. I wouldn't use the "restore a backup" strategy. Script all your schema changes, and have your CI server run those scripts on the database. Have a version table to keep track of the current database version, and only execute the scripts if they are for a newer version. Use a migr...
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What is a clearfix?

...of laying out elements.) A clearfix is a way for an element to automatically clear its child elements, so that you don't need to add additional markup. It's generally used in float layouts where elements are floated to be stacked horizontally. The clearfix is a way to combat the zero-height cont...
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Convert Python program to C/C++ code? [closed]

...t * stuff). And it will never get quite as fast as plain C because it's usually interfacing with Python (100% or more? only for plain numerical code that doesn't interface with Python at all for the most time!). But other than that, yes, it can get you a pretty devent speedup. –...
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C# Sortable collection which allows duplicate keys

... Use this Comparer e.g. with SortedLists or SortedDictionaries, that don't allow duplicate keys /// </summary> /// <typeparam name="TKey"></typeparam> public class DuplicateKeyComparer<TKey> : IComparer<TKey> where TKey : IComparable { #...