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Assign multiple columns using := in data.table, by group
...t(dim(get(objectName))),by=objectName]. Trouble is that as.list has call overhead and also copies the small vector. If efficiency is a problem as number of groups rises then please let us know.
– Matt Dowle
May 21 '14 at 11:49
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What is the difference between object keys with quotes and without quotes?
...xchange format does require double quotes around identifiers (and does not allow single quotes).
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Django URL Redirect
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You can try the Class Based View called RedirectView
from django.views.generic.base import RedirectView
urlpatterns = patterns('',
url(r'^$', 'macmonster.views.home'),
#url(r'^macmon_home$', 'macmonster.views.home'),
url(r'^macmon_output/$', 'ma...
Update parent scope variable in AngularJS
... Sorry I forgot about this question. I have accepted it because eventually I did manage to get it working with the help of this answer.
– Malcr001
Jun 13 '13 at 22:46
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How to install grunt and how to build script with it
Hi I'm trying to install Grunt on Windows 7 64 bit. I have installed Grunt using commands
4 Answers
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Full Page
I have the example code below. This works fine with all browsers except for browsers on mobile devices.
5 Answers
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Is there any Rails function to check if a partial exists?
..., I'm using the following in my Rails 3/3.1 projects:
lookup_context.find_all('posts/_form').any?
The advantage over other solutions I've seen is that this will look in all view paths instead of just your rails root. This is important to me as I have a lot of rails engines.
This also works in R...
Difference between __str__ and __repr__?
...e come right out and say it — I do not believe in debuggers. I don’t really know how to use any debugger, and have never used one seriously. Furthermore, I believe that the big fault in debuggers is their basic nature — most failures I debug happened a long long time ago, in a galaxy far far a...
Bash conditionals: how to “and” expressions? (if [ ! -z $VAR && -e $VAR ])
...te easily handle empty strings. If that's what you want then you don't actually need the -z non-empty check:
pax> VAR=xyzzy
pax> if [[ -e $VAR ]] ; then echo yes ; fi
pax> VAR=/tmp
pax> if [[ -e $VAR ]] ; then echo yes ; fi
yes
In other words, just use:
if [[ -e "$var" ]] ; then
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Chrome, Javascript, window.open in new tab
...pup’) by specifying options in the 3rd parameter
3. If the window.open call was not part of a user-initiated event, it’ll open in a new window.
4. A “user initiated event” does not have to the same function call – but it must originate in the function invoked by a user click
5. If a use...