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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 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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How do I open the SearchView programmatically?
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Works perfect, but only for API > 14. For earlier API you can use this: MenuItemCompat.expandActionView(searchMenuItem);
– Andrei Aulaska
May 29 '14 at 8:21
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Full examples of using pySerial package [closed]
...is code. I'm not certain on this but I believe the serial port is automatically opened when it is explicitly defined as you have done with ser. After commenting out the ser.open() line it worked.
– user3817250
Sep 23 '14 at 14:31
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add column to mysql table if it does not exist
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OK this is really crude but someone's got to say it. if you are simply running a SQL script from the command line, you can give mysql the --force switch, which means keep going even if there's an error. then, just go for it. you just want...
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...
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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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...
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() ...