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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable icc , will eliminate the library call for pow(a,6) .)
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How do I redirect in expressjs while passing some context?
...gs. You'll need to ensure that the values are properly encodeURIComponent and decodeURIComponent.
app.get('/category', function(req, res) {
var string = encodeURIComponent('something that would break');
res.redirect('/?valid=' + string);
});
You can snag that in your other route by getting t...
How to communicate between iframe and the parent site?
...bsite in the iframe isn't located in the same domain , but both are mine, and I would like to communicate between the iframe and the parent site. Is it possible?
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MIN/MAX vs ORDER BY and LIMIT
...d field, using MIN() requires a single full pass of the table. Using SORT and LIMIT requires a filesort. If run against a large table, there would likely be a significant difference in percieved performance. As a meaningless data point, MIN() took .36s while SORT and LIMIT took .84s against a 106...
Changing the default folder in Emacs
I am fairly new to Emacs and I have been trying to figure out how to change the default folder for C-x C-f on start-up. For instance when I first load Emacs and hit C-x C-f its default folder is C:\emacs\emacs-21.3\bin , but I would rather it be the desktop. I believe there is some way to custo...
Differences between “java -cp” and “java -jar”?
...he difference between running a Java application with java -cp CLASSPATH and java -jar JAR_FILE_PATH ? Is one of them preferred to the other for running a Java application? I mean which one of these ways is more expensive for JVM (according to their machine resources usage)?
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Optimal number of threads per core
Let's say I have a 4-core CPU, and I want to run some process in the minimum amount of time. The process is ideally parallelizable, so I can run chunks of it on an infinite number of threads and each thread takes the same amount of time.
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Remove non-numeric characters (except periods and commas) from a string
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You could use preg_replace to swap out all non-numeric characters and the comma and period/full stop as follows:
$testString = '12.322,11T';
echo preg_replace('/[^0-9,.]+/', '', $testString);
The pattern can also be expressed as /[^\d,.]+/
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Proper MIME media type for PDF files
When working with PDFs, I've run across the MIME types application/pdf and application/x-pdf among others.
3 Answers
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Sort JavaScript object by key
...swers to this question are outdated, never matched implementation reality, and have officially become incorrect now that the ES6/ES2015 spec has been published.
See the section on property iteration order in Exploring ES6 by Axel Rauschmayer:
All methods that iterate over property keys do so ...