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Count number of rows within each group
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I don't know but this could be useful as well... df %>% group_by(group, variable) %>% mutate(count = n())
– Manoj Kumar
Dec 14 '16 at 17:57
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Tuples( or arrays ) as Dictionary keys in C#
...string. I tried using arrays as keys, but that did not work, and I don't know what else to do. At this point I am considering making a Dictionary of Dictionaries of Dictionaries, but that would probably not be very pretty to look at, though it is how I would do it in javascript.
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C/C++ include header file order
...d either in the cpp or in the header itself. But I would be interested to know if that's what people think would work better in the long run... Why don't you post an answer with your proposal and we'll see who "wins"? ;-)
– squelart
May 4 '10 at 3:33
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How do I view events fired on an element in Chrome DevTools?
...ect wanted element) then go to Console tab and write:
monitorEvents($0)
Now when you move mouse over this element, focus or click it, the name of the fired event will be displayed with its data.
To stop getting this data just write this to console:
unmonitorEvents($0)
$0 is just the last DOM ...
.NET 4.0 build issues on CI server
...can install the "Microsoft Windows SDK for Windows 7 and .NET Framework 4" now.
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=6b6c21d2-2006-4afa-9702-529fa782d63b
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What is Common Gateway Interface (CGI)?
... the parameters via standard input and standard output so the program can know where and what to look for.
The main benefit is that you can run ANY executable code from the web, given that both the webserver and the program know how CGI works. That's why you could write web programs in C or Bash wi...
advantage of tap method in ruby
...iately clear. A reader would not have to read what is inside the block to know that an instance user is created.
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What is the difference between static func and class func in Swift?
...al. For more information. See nextD's answer below. Also x.dynamicType has now been replaced with type(of:x)
– Honey
Jan 16 '17 at 2:54
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android fragment- How to save states of views in a fragment when another fragment is pushed on top o
...dded to the backstack and another fragment (say FragB ) comes to the top. Now on hitting back FragA comes to the top and the onCreateView() is called. Now I had FragA in a particular state before FragB got pushed on top of it.
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How is attr_accessible used in Rails 4?
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Rails 4 now uses strong parameters.
Protecting attributes is now done in the controller. This is an example:
class PeopleController < ApplicationController
def create
Person.create(person_params)
end
private
def pe...