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How to initialize a List to a given size (as opposed to capacity)?
...htly faster too. Personally I find the code using Repeat more descriptive, and suspect that in the real world the performance difference would be irrelevant, but your mileage may vary.
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Will strlen be calculated multiple times if used in a loop condition?
...tion. If it might, then you'll need to either call strlen() each time, or handle it through more complicated logic.
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Best way to make Django's login_required the default
...und
matching URL patterns. To use, add the class to MIDDLEWARE_CLASSES and
define LOGIN_REQUIRED_URLS and LOGIN_REQUIRED_URLS_EXCEPTIONS in your
settings.py. For example:
------
LOGIN_REQUIRED_URLS = (
r'/topsecret/(.*)$',
)
LOGIN_REQUIRED_URLS_EXCEPTIONS = (
...
Android emulator freezing OS X v10.9 (Mavericks) with HAXM
I just updated to OS X v10.9 (Mavericks), and now whenever I start up any of my emulators, as soon as the emulator starts up, my entire computer freezes with a spinning progress indicator in the center of the screen (not a beachball, the progress indicator is similar to what you see when shutting...
LINQ, Where() vs FindAll()
Can someone explain how the LINQ functions Where(..) and FindAll(..) differ? They both seem to do the same thing...
4 Answe...
How to create named and latest tag in Docker?
...n image containing Node.js 0.10.24). I built that image using a Dockerfile and executing docker build and by providing a tag using the -t parameter.
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How can I count text lines inside an DOM element? Can I?
...using:
var divHeight = document.getElementById('content').offsetHeight;
And divide by the font line height:
document.getElementById('content').style.lineHeight;
Or to get the line height if it hasn't been explicitly set:
var element = document.getElementById('content');
document.defaultView.g...
What is the equivalent of “!=” in Excel VBA?
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Fun fact to back this answer: Visual Basic and Pascal languages store strings with their length in the beginning and the content itself right after that. C-based and Java languages, on the other hand, do not store the length and have the '\0' (null) terminator to sign...
Are PHP Variables passed by value or by reference?
...ave an argument to a function always passed by reference, prepend an ampersand (&) to the argument name in the function definition.
<?php
function add_some_extra(&$string)
{
$string .= 'and something extra.';
}
$str = 'This is a string, ';
add_some_extra($str);
echo $str; // out...
To find whether a column exists in data frame or not
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Assuming that the name of your data frame is dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
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