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Assign multiple columns using := in data.table, by group

...t(dim(get(objectName))),by=objectNa‌​me]. 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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background-size in shorthand background property (CSS3)

...you have in your question or my Code example. It's just not implemented in all browsers yet. – Kraz Oct 23 '11 at 6:37 ...
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Show diff between commits

... Try git diff k73ud^..dj374 to make sure to include all changes of k73ud in the resulting diff. git diff compares two endpoints (instead of a commit range). Since the OP want to see the changes introduced by k73ud, he/she needs to difference between the first parent commit of...
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Count occurrences of a char in a string using Bash

... you can for example remove all other chars and count the whats remains, like: var="text,text,text,text" res="${var//[^,]}" echo "$res" echo "${#res}" will print ,,, 3 or tr -dc ',' <<<"$var" | awk '{ print length; }' or tr -dc ',' &l...
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Converting PKCS#12 certificate into PEM using OpenSSL

... understand it as I am going to use it in future (to simplify my solution calling openssh as command) – Jan Vlcinsky May 8 '14 at 21:40 ...
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How to debug template binding errors for KnockoutJS?

... If you are using Chrome for development, there is a really great extension (with which I'm not affiliated) called Knockoutjs context debugger that shows you the binding context directly in the Developer Tools' Elements panel. ...
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Creating a URL in the controller .NET MVC

...Root" is the name of the route as defined in the RegisterRoutes method (usually in RouteConfig). For me, it was "Default" (as it was when I created my project). – Andy Sep 23 '14 at 15:51 ...
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Import Error: No module named numpy

...stion , but still one step behind. I have only one version of Python 3 installed on my Windows 7 ( sorry ) 64-bit system. 2...
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How can I make my match non greedy in vim?

...olve different problems so it makes sense that the syntax could be -potentially wildly- different across these implementations. We have to accept that this is just how the real world works even though it sometimes makes our lives harder as developers. Luckily many tools at least provide a Perl-com...
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Sleep Command in T-SQL?

... want to be able to run some tests to see if the asynchronous pattern is really going to make it more scalable. In order to "mock" an external service that is slow, I want to be able to call a SQL server with a script that runs slowly, but isn't actually processing a ton of stuff. ...