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Are list-comprehensions and functional functions faster than “for loops”?

...ike map() , filter() and reduce() faster than a for loop? Why, technically, they run in a C speed , while the for loop runs in the python virtual machine speed ?. ...
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How to change the name of a Django app?

...e changed the name of an app in Django by renaming its folder, imports and all its references (templates/indexes). But now I get this error when I try to run python manage.py runserver ...
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How to manually create icns files using iconutil?

...following instructions (link): Use iconutil to Create an icns File Manually The iconutil command-line tool converts iconset folders to deployment-ready, high-resolution icns files. (You can find complete documentation for this tool by entering man iconutil in Terminal.) Using this tool al...
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How does Python's super() work with multiple inheritance?

...ave trouble understanding the super() function (new style classes) especially when it comes to multiple inheritance. 16 A...
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What is the meaning of “__attribute__((packed, aligned(4))) ”

...gned(1))) sSampleStruct; so the above specified gcc attribute does not allow the structure padding. so the size will be 8 bytes. If you wish to do the same for all the structures, simply we can push the alignment value to stack using #pragma #pragma pack(push, 1) //Structure 1 ...... //Stru...
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What's the difference between utf8_general_ci and utf8_unicode_ci?

...languages or characters. On modern servers, this performance boost will be all but negligible. It was devised in a time when servers had a tiny fraction of the CPU performance of today's computers. Benefits of utf8mb4_unicode_ci over utf8mb4_general_ci utf8mb4_unicode_ci, which uses the Unicode r...
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Checking images for similarity with OpenCV

...he same image was passed twice, 0% would be returned if the images were totally different. 4 Answers ...
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Is it safe to push_back an element from the same vector?

If the second push_back causes a reallocation, the reference to the first integer in the vector will no longer be valid. So this isn't safe? ...
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java get file size efficiently

...97.044 URL sum: 95534, per Iteration: 382.136 File must be caching the calls to the filesystem, while channels and URL have some overhead. Code: import java.io.*; import java.net.*; import java.util.*; public enum FileSizeBench { LENGTH { @Override public long getResult() ...
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How to convert vector to array

...making a pointer that points to the actual array the vector is using internally. If you want to copy GMan's answer explains how – Michael Mrozek May 27 '10 at 17:22 4 ...