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Confusion between factor levels and factor labels
There seems to be a difference between levels and labels of a factor in R.
Up to now, I always thought that levels were the 'real' name of factor levels, and labels were the names used for output (such as tables and plots). Obviously, this is not the case, as the following example shows:
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Retina displays, high-res background images
...wer, here is the retina detection query I tend to use:
@media
only screen and (-webkit-min-device-pixel-ratio: 2),
only screen and ( min--moz-device-pixel-ratio: 2),
only screen and ( -o-min-device-pixel-ratio: 2/1),
only screen and ( min-device-pixel-ratio: 2),
only screen and ( ...
What is the difference between range and xrange functions in Python 2.X?
Apparently xrange is faster but I have no idea why it's faster (and no proof besides the anecdotal so far that it is faster) or what besides that is different about
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How do I safely pass objects, especially STL objects, to and from a DLL?
How do I pass class objects, especially STL objects, to and from a C++ DLL?
4 Answers
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git rebase, keeping track of 'local' and 'remote'
...se, I often have difficulty working out what is happening with the 'local' and 'remote' when resolving conflicts. I sometimes have the impression that they swap sides from one commit to the next.
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eval command in Bash and its typical uses
After reading the bash man pages and with respect to this post .
10 Answers
10
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Understanding ibeacon distancing
...estimates.
While the distance estimates are useful, they are not perfect, and require that you control for other variables. Be sure you read up on the complexities and limitations before misusing this.
When we were building the Android iBeacon library, we had to come up with our own independent a...
Getting the last element of a list
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some_list[-1] is the shortest and most Pythonic.
In fact, you can do much more with this syntax. The some_list[-n] syntax gets the nth-to-last element. So some_list[-1] gets the last element, some_list[-2] gets the second to last, etc, all the way down t...
What is the difference between '@' and '=' in directive scope in AngularJS?
I've read the AngularJS documentation on the topic carefully, and then fiddled around with a directive. Here's the fiddle .
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Random record from MongoDB
I am looking to get a random record from a huge (100 million record) mongodb .
26 Answers
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