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What's the fastest way to merge/join data.frames in R?
...version.string
# R version 2.15.1 (2012-06-22)
Please note that I don't know plyr well so please do check with Hadley before relying on the plyr timings here. Also note that the data.table do include the time to convert to data.table and set the key, for fareness.
This answer has been updated s...
Visual Studio: Multiple post-build commands?
...arating by newlines is easier to read, so you should prefer it. However I know at least one case when && is useful. It is the scenario, when you use property sheets to have different post-build steps on different machines. VS 2008 doesn't allow setting PostBuildStep in property sheets direct...
Python + Django page redirect
...date: Django 1.0
There is apparently a better way of doing this in Django now using generic views.
Example -
from django.views.generic.simple import redirect_to
urlpatterns = patterns('',
(r'^one/$', redirect_to, {'url': '/another/'}),
#etc...
)
There is more in the generic views d...
How can I declare and define multiple variables in one line using C++?
...InputValue, presentInputValue;) or if they just happen to be the same type now but don't really need to be (uint8_t height, width; might turn into uint8_t height; uint16_t width; in the future and should have been uint8_t height; uint8_t width; to begin with).
– altendky
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Java 8 stream's .min() and .max(): why does this compile?
...unctionality works in Java 8. It relies on a concept which is informally known as "single abstract method" interfaces, or "SAM" interfaces. The idea is that any interface with one abstract method can be automatically implemented by any lambda - or method reference - whose method signature is a mat...
Where does PostgreSQL store the database?
...ific folder is painful as someone else might have installed it for you and now you do not know the configuration, so following sql helps to save the time. :) Thanks Mike.
– Vishal
Jun 14 '13 at 8:54
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Extract month and year from a zoo::yearmon object
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I know the OP is using zoo here, but I found this thread googling for a standard ts solution for the same problem. So I thought I'd add a zoo-free answer for ts as well.
# create an example Date
date_1 <- as.Date("1990-01-...
Is there a unique Android device ID?
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It's known to be null sometimes, it's documented as "can change upon factory reset". Use at your own risk, and it can be easily changed on a rooted phone.
– Seva Alekseyev
Jun 23 '10 at 14:21
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jQuery Event : Detect changes to the html/text of a div
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This is the correct answer as this is now favoured over using DOMSubtreeModified
– Joel Davey
Oct 11 '18 at 11:56
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Which is a better way to check if an array has more than one element?
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@AlixAxel oh ok... wow thanks, didn't know that :o... In any case I'm just gonna leave it there in case OP wants to differentiate between a String and Array (regardless of size) Thanks for pointing that out :)
– Andreas Wong
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