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When is it appropriate to use UDP instead of TCP? [closed]
... I just now ran a test out of curiosity. The test read 1 million records (select * from sometable). I set the number of records to return with each individual client request to be 1, 10, and then 100 (three test runs with each protocol). The server was only two hops away over a 100Mbit LAN. The ...
How to 'bulk update' with Django?
...each essentially having the form of the first example above) + the initial SELECT-query.
If every row requires a unique value there is no way to avoid one query per update. Perhaps look into other architectures like CQRS/Event sourcing if you need performance in this latter case.
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Are there benefits of passing by pointer over passing by reference in C++?
...ng reference in C? I am using codeblock (mingw) latest version and in that selecting a C project. Still passing by reference (func (int& a)) works. Or is it available in C99 or C11 onwards?
– Jon Wheelock
Oct 12 '15 at 1:18
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How do I connect to a specific Wi-Fi network in Android programmatically?
...ows a list of Wi-Fi networks available and connect to whichever network is selected by the user.
10 Answers
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Installing SciPy and NumPy using pip
...dly cut'n'paste the shell commands - there will be a few lines you need to select depending on your architecture, etc., and you'll need to fix/add the correct directories that it incorrectly assumes as well.
The third thing you may need is to yum install numpy-f2py or the equivalent.
Oh, yes and l...
Specifying and saving a figure with exact size in pixels
...-- it seems that the DPI saved is always 0.02 pixels/inch smaller than the selected value, which will have a (small) effect on large image sizes. Some more discussion of this here.
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remove legend title in ggplot
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Since you may have more than one legends in a plot, a way to selectively remove just one of the titles without leaving an empty space is to set the name argument of the scale_ function to NULL, i.e.
scale_fill_discrete(name = NULL)
(kudos to @pascal for a comment on another thread)
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How to write a CSS hack for IE 11? [duplicate]
...this work because of the following:
When a user agent cannot parse the selector (i.e., it is not valid CSS 2.1), it must ignore the selector and the following declaration block (if any) as well.
<!doctype html>
<html>
<head>
<title>IE10/11 Media Query Test<...
LINQ OrderBy versus ThenBy
...e,
o.InvoiceOwner.FirstName,
o.InvoiceID
select o;
If you call OrderBy multiple times, it will effectively reorder the sequence completely three times... so the final call will effectively be the dominant one. You can (in LINQ to Objects) write
foo.OrderBy(x).O...
Does Python support multithreading? Can it speed up execution time?
...ross multiple cores. This extends to I/O controlled by the kernel, such as select() calls for socket reads and writes, making Python handle network events reasonably efficiently in a multi-threaded multi-core setup.
What many server deployments then do, is run more than one Python process, to let t...