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How do I filter ForeignKey choices in a Django ModelForm?

... can populate the validation data by making using the super(...).__init__ call in your overridden method. If you are making several of these queryset changes its a lot more elegant to package them by overriding the init method. – michael Aug 7 '09 at 4:53 ...
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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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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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Timer function to provide time in nano seconds using C++

...psets, so you may want to make sure you do not have those chipset. Additionally some dual core AMDs may also cause a problem. See the second post by sebbbi, where he states: QueryPerformanceCounter() and QueryPerformanceFrequency() offer a bit better resolution, but have different issues. ...
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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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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 ...
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What is the difference between g++ and gcc?

... was once upon a time just the GNU C Compiler). Even though they automatically determine which backends (cc1 cc1plus ...) to call depending on the file-type, unless overridden with -x language, they have some differences. The probably most important difference in their defaults is which libraries ...
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Is it possible to make abstract classes in Python?

...nitions of those methods: >>> Abstract() Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: Can't instantiate abstract class Abstract with abstract methods foo >>> class StillAbstract(Abstract): ... pass ... >>> StillAbstr...
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lodash multi-column sortBy descending

...dash.com/docs#orderBy) in Lodash as of 4.3.0. The normal sort function is called _.sortBy(lodash.com/docs#sortBy) – Nidhin David Feb 12 '16 at 11:19 2 ...