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Equivalent of “throw” in R
...does one "throw" an error in R? I have a function that takes a data frame and some column names and does stuff with them. If the columns don't exist, I want the function to stop and to stop all functions depending on it.
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jQuery or javascript to find memory usage of page
...use. Unfortunately, right now this is still a Chrome only feature (a non-standard extension of window.performance).
window.performance.memory
Browser support: Chrome 6+
2012 Answer
Is there a way to find out how much memory is being used by a web page, or by my jquery application? I'm look...
What's the best Django search app? [closed]
I'm building a Django project that needs search functionality, and until there's a django.contrib.search , I have to choose a search app. So, which is the best? By "best" I mean...
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Is there a naming convention for MySQL?
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I would say that first and foremost: be consistent.
I reckon you are almost there with the conventions that you have outlined in your question. A couple of comments though:
Points 1 and 2 are good I reckon.
Point 3 - sadly this is not always pos...
Can I safely delete contents of Xcode Derived data folder?
I am running low on disk space and checked through a third party utility that among other things that ~/Library/Developer/Xcode/DerivedData directory is taking about 22GB of disk space.
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What's the difference between a catalog and a schema in a relational database?
... other things--all of the various schemas (external, conceptual, internal) and all of the corresponding mappings (external/conceptual, conceptual/internal) are kept.
In other words, the catalog contains detailed information (sometimes called descriptor information or metadata) regarding the va...
Difference between getDefaultSharedPreferences and getSharedPreferences
What is the difference between getDefaultSharedPreferences and getSharedPreferences in Android? Can anyone please explain?
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Get average color of image via Javascript
...e.net/xLF38/818/
Note, this will only work with images on the same domain and in browsers that support HTML5 canvas:
function getAverageRGB(imgEl) {
var blockSize = 5, // only visit every 5 pixels
defaultRGB = {r:0,g:0,b:0}, // for non-supporting envs
canvas = document.createE...
MySQL: @variable vs. variable. What's the difference?
...are loosely typed variables that may be initialized somewhere in a session and keep their value until the session ends.
They are prepended with an @ sign, like this: @var
You can initialize this variable with a SET statement or inside a query:
SET @var = 1
SELECT @var2 := 2
When you develop a stor...
How to sort my paws?
...nt experiment runs stored as ascii arrays. Rather than try to copy-paste stand-alone code examples into this question, here's a bitbucket mercurial repository with full, stand-alone code. You can clone it with
hg clone https://joferkington@bitbucket.org/joferkington/paw-analysis
Overview
There...